/*
  * Copyright (c) 2006 Konstantin Shishkov
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 
 /**

  * @file

  * TIFF image decoder

  * @author Konstantin Shishkov
  */

 #include "config.h"

 #if CONFIG_ZLIB

 #include <zlib.h>
 #endif

 #if CONFIG_LZMA

 #define LZMA_API_STATIC

 #include <lzma.h>
 #endif

 #include "libavutil/attributes.h"

 #include "libavutil/avstring.h"

 #include "libavutil/intreadwrite.h"

 #include "libavutil/imgutils.h"

 #include "avcodec.h"

 #include "bytestream.h"

 #include "faxcompr.h"
 #include "internal.h"
 #include "lzw.h"
 #include "mathops.h"
 #include "tiff.h"

 #include "tiff_data.h"

 #include "thread.h"

 typedef struct TiffContext {
     AVCodecContext *avctx;

     GetByteContext gb;

 
     int width, height;

     unsigned int bpp, bppcount;

     uint32_t palette[256];
     int palette_is_set;

     int le;

     enum TiffCompr compr;

     enum TiffPhotometric photometric;

     int planar;

     int subsampling[2];

     int fax_opts;

     int predictor;

     int fill_order;

     uint32_t res[4];

     int strips, rps, sstype;

     int sot;

     int stripsizesoff, stripsize, stripoff, strippos;

     LZWState *lzw;

     uint8_t *deinvert_buf;
     int deinvert_buf_size;

     uint8_t *yuv_line;
     unsigned int yuv_line_size;

     uint8_t *fax_buffer;
     unsigned int fax_buffer_size;

     int geotag_count;
     TiffGeoTag *geotags;

 } TiffContext;
 

 static void free_geotags(TiffContext *const s)
 {
     int i;
     for (i = 0; i < s->geotag_count; i++) {
         if (s->geotags[i].val)
             av_freep(&s->geotags[i].val);
     }
     av_freep(&s->geotags);

     s->geotag_count = 0;

 }
 
 #define RET_GEOKEY(TYPE, array, element)\
     if (key >= TIFF_##TYPE##_KEY_ID_OFFSET &&\
         key - TIFF_##TYPE##_KEY_ID_OFFSET < FF_ARRAY_ELEMS(ff_tiff_##array##_name_type_map))\
         return ff_tiff_##array##_name_type_map[key - TIFF_##TYPE##_KEY_ID_OFFSET].element;
 
 static const char *get_geokey_name(int key)
 {
     RET_GEOKEY(VERT, vert, name);
     RET_GEOKEY(PROJ, proj, name);
     RET_GEOKEY(GEOG, geog, name);
     RET_GEOKEY(CONF, conf, name);
 
     return NULL;
 }
 
 static int get_geokey_type(int key)
 {
     RET_GEOKEY(VERT, vert, type);
     RET_GEOKEY(PROJ, proj, type);
     RET_GEOKEY(GEOG, geog, type);
     RET_GEOKEY(CONF, conf, type);
 
     return AVERROR_INVALIDDATA;
 }
 
 static int cmp_id_key(const void *id, const void *k)
 {
     return *(const int*)id - ((const TiffGeoTagKeyName*)k)->key;
 }
 
 static const char *search_keyval(const TiffGeoTagKeyName *keys, int n, int id)
 {

     TiffGeoTagKeyName *r = bsearch(&id, keys, n, sizeof(keys[0]), cmp_id_key);
     if(r)
         return r->name;
 
     return NULL;

 }
 
 static char *get_geokey_val(int key, int val)
 {
     char *ap;
 
     if (val == TIFF_GEO_KEY_UNDEFINED)
         return av_strdup("undefined");
     if (val == TIFF_GEO_KEY_USER_DEFINED)
         return av_strdup("User-Defined");
 
 #define RET_GEOKEY_VAL(TYPE, array)\
     if (val >= TIFF_##TYPE##_OFFSET &&\
         val - TIFF_##TYPE##_OFFSET < FF_ARRAY_ELEMS(ff_tiff_##array##_codes))\
         return av_strdup(ff_tiff_##array##_codes[val - TIFF_##TYPE##_OFFSET]);
 
     switch (key) {
     case TIFF_GT_MODEL_TYPE_GEOKEY:
         RET_GEOKEY_VAL(GT_MODEL_TYPE, gt_model_type);
         break;
     case TIFF_GT_RASTER_TYPE_GEOKEY:
         RET_GEOKEY_VAL(GT_RASTER_TYPE, gt_raster_type);
         break;
     case TIFF_GEOG_LINEAR_UNITS_GEOKEY:
     case TIFF_PROJ_LINEAR_UNITS_GEOKEY:
     case TIFF_VERTICAL_UNITS_GEOKEY:
         RET_GEOKEY_VAL(LINEAR_UNIT, linear_unit);
         break;
     case TIFF_GEOG_ANGULAR_UNITS_GEOKEY:
     case TIFF_GEOG_AZIMUTH_UNITS_GEOKEY:
         RET_GEOKEY_VAL(ANGULAR_UNIT, angular_unit);
         break;
     case TIFF_GEOGRAPHIC_TYPE_GEOKEY:
         RET_GEOKEY_VAL(GCS_TYPE, gcs_type);
         RET_GEOKEY_VAL(GCSE_TYPE, gcse_type);
         break;
     case TIFF_GEOG_GEODETIC_DATUM_GEOKEY:
         RET_GEOKEY_VAL(GEODETIC_DATUM, geodetic_datum);
         RET_GEOKEY_VAL(GEODETIC_DATUM_E, geodetic_datum_e);
         break;
     case TIFF_GEOG_ELLIPSOID_GEOKEY:
         RET_GEOKEY_VAL(ELLIPSOID, ellipsoid);
         break;
     case TIFF_GEOG_PRIME_MERIDIAN_GEOKEY:
         RET_GEOKEY_VAL(PRIME_MERIDIAN, prime_meridian);
         break;
     case TIFF_PROJECTED_CS_TYPE_GEOKEY:

         ap = av_strdup(search_keyval(ff_tiff_proj_cs_type_codes, FF_ARRAY_ELEMS(ff_tiff_proj_cs_type_codes), val));
         if(ap) return ap;

         break;
     case TIFF_PROJECTION_GEOKEY:

         ap = av_strdup(search_keyval(ff_tiff_projection_codes, FF_ARRAY_ELEMS(ff_tiff_projection_codes), val));
         if(ap) return ap;

         break;
     case TIFF_PROJ_COORD_TRANS_GEOKEY:
         RET_GEOKEY_VAL(COORD_TRANS, coord_trans);
         break;
     case TIFF_VERTICAL_CS_TYPE_GEOKEY:
         RET_GEOKEY_VAL(VERT_CS, vert_cs);
         RET_GEOKEY_VAL(ORTHO_VERT_CS, ortho_vert_cs);
         break;
 
     }
 
     ap = av_malloc(14);
     if (ap)
         snprintf(ap, 14, "Unknown-%d", val);
     return ap;
 }
 
 static char *doubles2str(double *dp, int count, const char *sep)
 {
     int i;
     char *ap, *ap0;

     uint64_t component_len;

     if (!sep) sep = ", ";

     component_len = 24LL + strlen(sep);

     if (count >= (INT_MAX - 1)/component_len)
         return NULL;
     ap = av_malloc(component_len * count + 1);

     if (!ap)
         return NULL;
     ap0   = ap;
     ap[0] = '\0';
     for (i = 0; i < count; i++) {

         unsigned l = snprintf(ap, component_len, "%.15g%s", dp[i], sep);

         if(l >= component_len) {
             av_free(ap0);

             return NULL;

         }

         ap += l;
     }
     ap0[strlen(ap0) - strlen(sep)] = '\0';
     return ap0;
 }
 

 static int add_metadata(int count, int type,

                         const char *name, const char *sep, TiffContext *s, AVFrame *frame)

 {
     switch(type) {

     case TIFF_DOUBLE: return ff_tadd_doubles_metadata(count, name, sep, &s->gb, s->le, &frame->metadata);
     case TIFF_SHORT : return ff_tadd_shorts_metadata(count, name, sep, &s->gb, s->le, 0, &frame->metadata);
     case TIFF_STRING: return ff_tadd_string_metadata(count, name, &s->gb, s->le, &frame->metadata);

     default         : return AVERROR_INVALIDDATA;
     };
 }
 

 static void av_always_inline horizontal_fill(unsigned int bpp, uint8_t* dst,
                                              int usePtr, const uint8_t *src,
                                              uint8_t c, int width, int offset)
 {

     switch (bpp) {

     case 1:
         while (--width >= 0) {
             dst[(width+offset)*8+7] = (usePtr ? src[width] : c)      & 0x1;
             dst[(width+offset)*8+6] = (usePtr ? src[width] : c) >> 1 & 0x1;
             dst[(width+offset)*8+5] = (usePtr ? src[width] : c) >> 2 & 0x1;
             dst[(width+offset)*8+4] = (usePtr ? src[width] : c) >> 3 & 0x1;
             dst[(width+offset)*8+3] = (usePtr ? src[width] : c) >> 4 & 0x1;
             dst[(width+offset)*8+2] = (usePtr ? src[width] : c) >> 5 & 0x1;
             dst[(width+offset)*8+1] = (usePtr ? src[width] : c) >> 6 & 0x1;
             dst[(width+offset)*8+0] = (usePtr ? src[width] : c) >> 7;
         }
         break;

     case 2:

         while (--width >= 0) {
             dst[(width+offset)*4+3] = (usePtr ? src[width] : c) & 0x3;
             dst[(width+offset)*4+2] = (usePtr ? src[width] : c) >> 2 & 0x3;
             dst[(width+offset)*4+1] = (usePtr ? src[width] : c) >> 4 & 0x3;
             dst[(width+offset)*4+0] = (usePtr ? src[width] : c) >> 6;

         }

         break;
     case 4:

         while (--width >= 0) {
             dst[(width+offset)*2+1] = (usePtr ? src[width] : c) & 0xF;
             dst[(width+offset)*2+0] = (usePtr ? src[width] : c) >> 4;

         }

         break;
     default:

         if (usePtr) {
             memcpy(dst + offset, src, width);
         } else {
             memset(dst + offset, c, width);
         }
     }
 }
 

 static int deinvert_buffer(TiffContext *s, const uint8_t *src, int size)
 {
     int i;
 
     av_fast_padded_malloc(&s->deinvert_buf, &s->deinvert_buf_size, size);
     if (!s->deinvert_buf)
         return AVERROR(ENOMEM);
     for (i = 0; i < size; i++)
         s->deinvert_buf[i] = ff_reverse[src[i]];
 
     return 0;
 }
 

 static void unpack_yuv(TiffContext *s, AVFrame *p,
                        const uint8_t *src, int lnum)
 {
     int i, j, k;
     int w       = (s->width - 1) / s->subsampling[0] + 1;
     uint8_t *pu = &p->data[1][lnum / s->subsampling[1] * p->linesize[1]];
     uint8_t *pv = &p->data[2][lnum / s->subsampling[1] * p->linesize[2]];
     if (s->width % s->subsampling[0] || s->height % s->subsampling[1]) {
         for (i = 0; i < w; i++) {
             for (j = 0; j < s->subsampling[1]; j++)
                 for (k = 0; k < s->subsampling[0]; k++)
                     p->data[0][FFMIN(lnum + j, s->height-1) * p->linesize[0] +
                                FFMIN(i * s->subsampling[0] + k, s->width-1)] = *src++;
             *pu++ = *src++;
             *pv++ = *src++;
         }
     }else{
         for (i = 0; i < w; i++) {
             for (j = 0; j < s->subsampling[1]; j++)
                 for (k = 0; k < s->subsampling[0]; k++)
                     p->data[0][(lnum + j) * p->linesize[0] +
                                i * s->subsampling[0] + k] = *src++;
             *pu++ = *src++;
             *pv++ = *src++;
         }
     }
 }
 

 #if CONFIG_ZLIB

 static int tiff_uncompress(uint8_t *dst, unsigned long *len, const uint8_t *src,
                            int size)

 {

     z_stream zstream = { 0 };

     int zret;
 

     zstream.next_in   = (uint8_t *)src;

     zstream.avail_in  = size;
     zstream.next_out  = dst;

     zstream.avail_out = *len;

     zret              = inflateInit(&zstream);

     if (zret != Z_OK) {
         av_log(NULL, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
         return zret;
     }
     zret = inflate(&zstream, Z_SYNC_FLUSH);
     inflateEnd(&zstream);
     *len = zstream.total_out;
     return zret == Z_STREAM_END ? Z_OK : zret;
 }

 static int tiff_unpack_zlib(TiffContext *s, AVFrame *p, uint8_t *dst, int stride,
                             const uint8_t *src, int size, int width, int lines,
                             int strip_start, int is_yuv)

 {
     uint8_t *zbuf;
     unsigned long outlen;
     int ret, line;
     outlen = width * lines;
     zbuf   = av_malloc(outlen);
     if (!zbuf)
         return AVERROR(ENOMEM);

     if (s->fill_order) {
         if ((ret = deinvert_buffer(s, src, size)) < 0) {
             av_free(zbuf);
             return ret;
         }
         src = s->deinvert_buf;
     }

     ret = tiff_uncompress(zbuf, &outlen, src, size);
     if (ret != Z_OK) {
         av_log(s->avctx, AV_LOG_ERROR,
                "Uncompressing failed (%lu of %lu) with error %d\n", outlen,
                (unsigned long)width * lines, ret);
         av_free(zbuf);
         return AVERROR_UNKNOWN;
     }
     src = zbuf;
     for (line = 0; line < lines; line++) {

         if (s->bpp < 8 && s->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
             horizontal_fill(s->bpp, dst, 1, src, 0, width, 0);
         } else {
             memcpy(dst, src, width);
         }

         if (is_yuv) {
             unpack_yuv(s, p, dst, strip_start + line);
             line += s->subsampling[1] - 1;
         }

         dst += stride;
         src += width;
     }
     av_free(zbuf);
     return 0;
 }

 #endif

 #if CONFIG_LZMA
 static int tiff_uncompress_lzma(uint8_t *dst, uint64_t *len, const uint8_t *src,
                                 int size)
 {
     lzma_stream stream = LZMA_STREAM_INIT;
     lzma_ret ret;
 
     stream.next_in   = (uint8_t *)src;
     stream.avail_in  = size;
     stream.next_out  = dst;
     stream.avail_out = *len;
     ret              = lzma_stream_decoder(&stream, UINT64_MAX, 0);
     if (ret != LZMA_OK) {
         av_log(NULL, AV_LOG_ERROR, "LZMA init error: %d\n", ret);
         return ret;
     }
     ret = lzma_code(&stream, LZMA_RUN);
     lzma_end(&stream);
     *len = stream.total_out;
     return ret == LZMA_STREAM_END ? LZMA_OK : ret;
 }
 
 static int tiff_unpack_lzma(TiffContext *s, AVFrame *p, uint8_t *dst, int stride,
                             const uint8_t *src, int size, int width, int lines,
                             int strip_start, int is_yuv)
 {

     uint64_t outlen = width * (uint64_t)lines;

     int ret, line;
     uint8_t *buf = av_malloc(outlen);
     if (!buf)
         return AVERROR(ENOMEM);
     if (s->fill_order) {
         if ((ret = deinvert_buffer(s, src, size)) < 0) {
             av_free(buf);
             return ret;
         }
         src = s->deinvert_buf;
     }
     ret = tiff_uncompress_lzma(buf, &outlen, src, size);
     if (ret != LZMA_OK) {
         av_log(s->avctx, AV_LOG_ERROR,
                "Uncompressing failed (%"PRIu64" of %"PRIu64") with error %d\n", outlen,
                (uint64_t)width * lines, ret);
         av_free(buf);
         return AVERROR_UNKNOWN;
     }
     src = buf;
     for (line = 0; line < lines; line++) {
         if (s->bpp < 8 && s->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
             horizontal_fill(s->bpp, dst, 1, src, 0, width, 0);
         } else {
             memcpy(dst, src, width);
         }
         if (is_yuv) {
             unpack_yuv(s, p, dst, strip_start + line);
             line += s->subsampling[1] - 1;
         }
         dst += stride;
         src += width;
     }
     av_free(buf);
     return 0;
 }
 #endif

 
 static int tiff_unpack_fax(TiffContext *s, uint8_t *dst, int stride,

                            const uint8_t *src, int size, int width, int lines)

 {
     int i, ret = 0;

     int line;

     uint8_t *src2;
 
     av_fast_padded_malloc(&s->fax_buffer, &s->fax_buffer_size, size);
     src2 = s->fax_buffer;

 
     if (!src2) {
         av_log(s->avctx, AV_LOG_ERROR,
                "Error allocating temporary buffer\n");
         return AVERROR(ENOMEM);
     }

     if (!s->fill_order) {
         memcpy(src2, src, size);
     } else {
         for (i = 0; i < size; i++)
             src2[i] = ff_reverse[src[i]];
     }

     memset(src2 + size, 0, AV_INPUT_BUFFER_PADDING_SIZE);

     ret = ff_ccitt_unpack(s->avctx, src2, size, dst, lines, stride,
                           s->compr, s->fax_opts);

     if (s->bpp < 8 && s->avctx->pix_fmt == AV_PIX_FMT_PAL8)
         for (line = 0; line < lines; line++) {
             horizontal_fill(s->bpp, dst, 1, dst, 0, width, 0);
             dst += stride;
         }

     return ret;
 }
 

 static int tiff_unpack_strip(TiffContext *s, AVFrame *p, uint8_t *dst, int stride,
                              const uint8_t *src, int size, int strip_start, int lines)

 {

     PutByteContext pb;

     int c, line, pixels, code, ret;

     const uint8_t *ssrc = src;

     int width = ((s->width * s->bpp) + 7) >> 3;

     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(p->format);

     int is_yuv = !(desc->flags & AV_PIX_FMT_FLAG_RGB) &&
                  (desc->flags & AV_PIX_FMT_FLAG_PLANAR) &&
                  desc->nb_components >= 3;

     if (s->planar)
         width /= s->bppcount;
 

     if (size <= 0)
         return AVERROR_INVALIDDATA;
 

     if (is_yuv) {
         int bytes_per_row = (((s->width - 1) / s->subsampling[0] + 1) * s->bpp *
                             s->subsampling[0] * s->subsampling[1] + 7) >> 3;
         av_fast_padded_malloc(&s->yuv_line, &s->yuv_line_size, bytes_per_row);
         if (s->yuv_line == NULL) {
             av_log(s->avctx, AV_LOG_ERROR, "Not enough memory\n");
             return AVERROR(ENOMEM);
         }
         dst = s->yuv_line;
         stride = 0;

 
         width = (s->width - 1) / s->subsampling[0] + 1;
         width = width * s->subsampling[0] * s->subsampling[1] + 2*width;

         av_assert0(width <= bytes_per_row);
         av_assert0(s->bpp == 24);
     }
 

     if (s->compr == TIFF_DEFLATE || s->compr == TIFF_ADOBE_DEFLATE) {

 #if CONFIG_ZLIB

         return tiff_unpack_zlib(s, p, dst, stride, src, size, width, lines,
                                 strip_start, is_yuv);

 #else
         av_log(s->avctx, AV_LOG_ERROR,
                "zlib support not enabled, "
                "deflate compression not supported\n");
         return AVERROR(ENOSYS);

 #endif

     }

     if (s->compr == TIFF_LZMA) {
 #if CONFIG_LZMA
         return tiff_unpack_lzma(s, p, dst, stride, src, size, width, lines,
                                 strip_start, is_yuv);
 #else
         av_log(s->avctx, AV_LOG_ERROR,
                "LZMA support not enabled\n");
         return AVERROR(ENOSYS);
 #endif
     }

     if (s->compr == TIFF_LZW) {

         if (s->fill_order) {

             if ((ret = deinvert_buffer(s, src, size)) < 0)
                 return ret;
             ssrc = src = s->deinvert_buf;

         }

         if (size > 1 && !src[0] && (src[1]&1)) {
             av_log(s->avctx, AV_LOG_ERROR, "Old style LZW is unsupported\n");
         }

         if ((ret = ff_lzw_decode_init(s->lzw, 8, src, size, FF_LZW_TIFF)) < 0) {

             av_log(s->avctx, AV_LOG_ERROR, "Error initializing LZW decoder\n");

             return ret;

         }

         for (line = 0; line < lines; line++) {
             pixels = ff_lzw_decode(s->lzw, dst, width);
             if (pixels < width) {
                 av_log(s->avctx, AV_LOG_ERROR, "Decoded only %i bytes of %i\n",
                        pixels, width);
                 return AVERROR_INVALIDDATA;
             }

             if (s->bpp < 8 && s->avctx->pix_fmt == AV_PIX_FMT_PAL8)
                 horizontal_fill(s->bpp, dst, 1, dst, 0, width, 0);

             if (is_yuv) {
                 unpack_yuv(s, p, dst, strip_start + line);
                 line += s->subsampling[1] - 1;
             }

             dst += stride;
         }
         return 0;

     }

     if (s->compr == TIFF_CCITT_RLE ||
         s->compr == TIFF_G3        ||
         s->compr == TIFF_G4) {

         if (is_yuv || p->format == AV_PIX_FMT_GRAY12)

             return AVERROR_INVALIDDATA;
 

         return tiff_unpack_fax(s, dst, stride, src, size, width, lines);

     }

 
     bytestream2_init(&s->gb, src, size);

     bytestream2_init_writer(&pb, dst, is_yuv ? s->yuv_line_size : (stride * lines));

     for (line = 0; line < lines; line++) {
         if (src - ssrc > size) {

             av_log(s->avctx, AV_LOG_ERROR, "Source data overread\n");

             return AVERROR_INVALIDDATA;

         }

         if (bytestream2_get_bytes_left(&s->gb) == 0 || bytestream2_get_eof(&pb))
             break;
         bytestream2_seek_p(&pb, stride * line, SEEK_SET);

         switch (s->compr) {

         case TIFF_RAW:

             if (ssrc + size - src < width)
                 return AVERROR_INVALIDDATA;

             if (!s->fill_order) {

                 horizontal_fill(s->bpp * (s->avctx->pix_fmt == AV_PIX_FMT_PAL8),

                                 dst, 1, src, 0, width, 0);

             } else {
                 int i;
                 for (i = 0; i < width; i++)

                     dst[i] = ff_reverse[src[i]];

             }

             src += width;

             break;
         case TIFF_PACKBITS:

             for (pixels = 0; pixels < width;) {

                 if (ssrc + size - src < 2) {
                     av_log(s->avctx, AV_LOG_ERROR, "Read went out of bounds\n");
                     return AVERROR_INVALIDDATA;
                 }

                 code = s->fill_order ? (int8_t) ff_reverse[*src++]: (int8_t) *src++;

                 if (code >= 0) {

                     code++;

                     if (pixels + code > width ||
                         ssrc + size - src < code) {

                         av_log(s->avctx, AV_LOG_ERROR,
                                "Copy went out of bounds\n");

                         return AVERROR_INVALIDDATA;

                     }

                     horizontal_fill(s->bpp * (s->avctx->pix_fmt == AV_PIX_FMT_PAL8),

                                     dst, 1, src, 0, code, pixels);

                     src    += code;

                     pixels += code;

                 } else if (code != -128) { // -127..-1

                     code = (-code) + 1;

                     if (pixels + code > width) {
                         av_log(s->avctx, AV_LOG_ERROR,
                                "Run went out of bounds\n");

                         return AVERROR_INVALIDDATA;

                     }
                     c = *src++;

                     horizontal_fill(s->bpp * (s->avctx->pix_fmt == AV_PIX_FMT_PAL8),

                                     dst, 0, NULL, c, code, pixels);

                     pixels += code;
                 }
             }

             if (s->fill_order) {
                 int i;
                 for (i = 0; i < width; i++)
                     dst[i] = ff_reverse[dst[i]];
             }

             break;
         }

         if (is_yuv) {
             unpack_yuv(s, p, dst, strip_start + line);
             line += s->subsampling[1] - 1;
         }

         dst += stride;
     }
     return 0;
 }
 

 static int init_image(TiffContext *s, ThreadFrame *frame)

 {

     int ret;

     int create_gray_palette = 0;

     // make sure there is no aliasing in the following switch
     if (s->bpp >= 100 || s->bppcount >= 10) {
         av_log(s->avctx, AV_LOG_ERROR,
                "Unsupported image parameters: bpp=%d, bppcount=%d\n",
                s->bpp, s->bppcount);
         return AVERROR_INVALIDDATA;
     }
 

     switch (s->planar * 1000 + s->bpp * 10 + s->bppcount) {

     case 11:

         if (!s->palette_is_set) {

             s->avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;

             break;
         }

     case 21:
     case 41:

         s->avctx->pix_fmt = AV_PIX_FMT_PAL8;
         if (!s->palette_is_set) {
             create_gray_palette = 1;
         }
         break;

     case 81:

         s->avctx->pix_fmt = s->palette_is_set ? AV_PIX_FMT_PAL8 : AV_PIX_FMT_GRAY8;

         break;
     case 243:

         if (s->photometric == TIFF_PHOTOMETRIC_YCBCR) {
             if (s->subsampling[0] == 1 && s->subsampling[1] == 1) {
                 s->avctx->pix_fmt = AV_PIX_FMT_YUV444P;

             } else if (s->subsampling[0] == 2 && s->subsampling[1] == 1) {
                 s->avctx->pix_fmt = AV_PIX_FMT_YUV422P;
             } else if (s->subsampling[0] == 4 && s->subsampling[1] == 1) {
                 s->avctx->pix_fmt = AV_PIX_FMT_YUV411P;

             } else if (s->subsampling[0] == 1 && s->subsampling[1] == 2) {
                 s->avctx->pix_fmt = AV_PIX_FMT_YUV440P;

             } else if (s->subsampling[0] == 2 && s->subsampling[1] == 2) {
                 s->avctx->pix_fmt = AV_PIX_FMT_YUV420P;

             } else if (s->subsampling[0] == 4 && s->subsampling[1] == 4) {
                 s->avctx->pix_fmt = AV_PIX_FMT_YUV410P;

             } else {
                 av_log(s->avctx, AV_LOG_ERROR, "Unsupported YCbCr subsampling\n");
                 return AVERROR_PATCHWELCOME;
             }
         } else
             s->avctx->pix_fmt = AV_PIX_FMT_RGB24;

         break;
     case 161:

         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_GRAY16LE : AV_PIX_FMT_GRAY16BE;

         break;

     case 162:

         s->avctx->pix_fmt = AV_PIX_FMT_YA8;

         break;

     case 322:
         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_YA16LE : AV_PIX_FMT_YA16BE;
         break;

     case 324:

         s->avctx->pix_fmt = AV_PIX_FMT_RGBA;

         break;
     case 483:

         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_RGB48LE  : AV_PIX_FMT_RGB48BE;

         break;

     case 644:

         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_RGBA64LE  : AV_PIX_FMT_RGBA64BE;
         break;
     case 1243:
         s->avctx->pix_fmt = AV_PIX_FMT_GBRP;
         break;
     case 1324:
         s->avctx->pix_fmt = AV_PIX_FMT_GBRAP;
         break;
     case 1483:
         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_GBRP16LE : AV_PIX_FMT_GBRP16BE;
         break;
     case 1644:
         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_GBRAP16LE : AV_PIX_FMT_GBRAP16BE;

         break;

     default:
         av_log(s->avctx, AV_LOG_ERROR,
                "This format is not supported (bpp=%d, bppcount=%d)\n",
                s->bpp, s->bppcount);
         return AVERROR_INVALIDDATA;
     }

 
     if (s->photometric == TIFF_PHOTOMETRIC_YCBCR) {
         const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(s->avctx->pix_fmt);

         if((desc->flags & AV_PIX_FMT_FLAG_RGB) ||
            !(desc->flags & AV_PIX_FMT_FLAG_PLANAR) ||
            desc->nb_components < 3) {

             av_log(s->avctx, AV_LOG_ERROR, "Unsupported YCbCr variant\n");
             return AVERROR_INVALIDDATA;
         }
     }
 

     if (s->width != s->avctx->width || s->height != s->avctx->height) {

         ret = ff_set_dimensions(s->avctx, s->width, s->height);
         if (ret < 0)

             return ret;
     }

     if ((ret = ff_thread_get_buffer(s->avctx, frame, 0)) < 0)

         return ret;

     if (s->avctx->pix_fmt == AV_PIX_FMT_PAL8) {

         if (!create_gray_palette)
             memcpy(frame->f->data[1], s->palette, sizeof(s->palette));
         else {
             /* make default grayscale pal */
             int i;
             uint32_t *pal = (uint32_t *)frame->f->data[1];
             for (i = 0; i < 1<<s->bpp; i++)
                 pal[i] = 0xFFU << 24 | i * 255 / ((1<<s->bpp) - 1) * 0x010101;
         }

     }
     return 0;
 }

 static void set_sar(TiffContext *s, unsigned tag, unsigned num, unsigned den)
 {
     int offset = tag == TIFF_YRES ? 2 : 0;
     s->res[offset++] = num;
     s->res[offset]   = den;

     if (s->res[0] && s->res[1] && s->res[2] && s->res[3]) {
         uint64_t num = s->res[2] * (uint64_t)s->res[1];
         uint64_t den = s->res[0] * (uint64_t)s->res[3];
         if (num > INT64_MAX || den > INT64_MAX) {
             num = num >> 1;
             den = den >> 1;
         }

         av_reduce(&s->avctx->sample_aspect_ratio.num, &s->avctx->sample_aspect_ratio.den,

                   num, den, INT32_MAX);
         if (!s->avctx->sample_aspect_ratio.den)
             s->avctx->sample_aspect_ratio = (AVRational) {0, 1};
     }

 }
 

 static int tiff_decode_tag(TiffContext *s, AVFrame *frame)

 {

     unsigned tag, type, count, off, value = 0, value2 = 0;

     int i, start;

     int pos;

     int ret;
     double *dp;

     ret = ff_tread_tag(&s->gb, s->le, &tag, &type, &count, &start);
     if (ret < 0) {

         goto end;

     }
 

     off = bytestream2_tell(&s->gb);

     if (count == 1) {
         switch (type) {

         case TIFF_BYTE:
         case TIFF_SHORT:
         case TIFF_LONG:

             value = ff_tget(&s->gb, type, s->le);

             break;

         case TIFF_RATIONAL:
             value  = ff_tget(&s->gb, TIFF_LONG, s->le);
             value2 = ff_tget(&s->gb, TIFF_LONG, s->le);
             break;

         case TIFF_STRING:

             if (count <= 4) {

                 break;
             }

         default:

             value = UINT_MAX;

         }
     }
 

     switch (tag) {

     case TIFF_WIDTH:
         s->width = value;
         break;
     case TIFF_HEIGHT:
         s->height = value;
         break;
     case TIFF_BPP:

         if (count > 4U) {

             av_log(s->avctx, AV_LOG_ERROR,
                    "This format is not supported (bpp=%d, %d components)\n",

                    value, count);

             return AVERROR_INVALIDDATA;

         }

         s->bppcount = count;

         if (count == 1)
             s->bpp = value;
         else {
             switch (type) {

             case TIFF_BYTE:
             case TIFF_SHORT:
             case TIFF_LONG:

                 s->bpp = 0;

                 if (bytestream2_get_bytes_left(&s->gb) < type_sizes[type] * count)

                     return AVERROR_INVALIDDATA;

                 for (i = 0; i < count; i++)

                     s->bpp += ff_tget(&s->gb, type, s->le);

                 break;
             default:
                 s->bpp = -1;
             }
         }

         break;
     case TIFF_SAMPLES_PER_PIXEL:
         if (count != 1) {
             av_log(s->avctx, AV_LOG_ERROR,
                    "Samples per pixel requires a single value, many provided\n");
             return AVERROR_INVALIDDATA;

         }

         if (value > 4U) {
             av_log(s->avctx, AV_LOG_ERROR,
                    "Samples per pixel %d is too large\n", value);
             return AVERROR_INVALIDDATA;
         }

         if (s->bppcount == 1)
             s->bpp *= value;
         s->bppcount = value;

         break;
     case TIFF_COMPR:

         s->compr     = value;

         av_log(s->avctx, AV_LOG_DEBUG, "compression: %d\n", s->compr);

         s->predictor = 0;

         switch (s->compr) {

         case TIFF_RAW:
         case TIFF_PACKBITS:

         case TIFF_LZW:

         case TIFF_CCITT_RLE:
             break;
         case TIFF_G3:
         case TIFF_G4:
             s->fax_opts = 0;

             break;
         case TIFF_DEFLATE:
         case TIFF_ADOBE_DEFLATE:

 #if CONFIG_ZLIB

             break;
 #else
             av_log(s->avctx, AV_LOG_ERROR, "Deflate: ZLib not compiled in\n");

             return AVERROR(ENOSYS);

 #endif

         case TIFF_JPEG:
         case TIFF_NEWJPEG:

             avpriv_report_missing_feature(s->avctx, "JPEG compression");

             return AVERROR_PATCHWELCOME;

         case TIFF_LZMA:

 #if CONFIG_LZMA
             break;
 #else
             av_log(s->avctx, AV_LOG_ERROR, "LZMA not compiled in\n");
             return AVERROR(ENOSYS);
 #endif

         default:

             av_log(s->avctx, AV_LOG_ERROR, "Unknown compression method %i\n",
                    s->compr);

             return AVERROR_INVALIDDATA;

         }
         break;
     case TIFF_ROWSPERSTRIP:

         if (!value || (type == TIFF_LONG && value == UINT_MAX))

             value = s->height;

         s->rps = FFMIN(value, s->height);

         break;
     case TIFF_STRIP_OFFS:

         if (count == 1) {

             if (value > INT_MAX) {
                 av_log(s->avctx, AV_LOG_ERROR,
                     "strippos %u too large\n", value);
                 return AVERROR_INVALIDDATA;
             }

             s->strippos = 0;
             s->stripoff = value;

         } else

             s->strippos = off;

         s->strips = count;

         if (s->strips == 1)
             s->rps = s->height;

         s->sot = type;
         break;
     case TIFF_STRIP_SIZE:

         if (count == 1) {

             if (value > INT_MAX) {
                 av_log(s->avctx, AV_LOG_ERROR,
                     "stripsize %u too large\n", value);
                 return AVERROR_INVALIDDATA;
             }

             s->stripsizesoff = 0;

             s->stripsize     = value;
             s->strips        = 1;

         } else {

             s->stripsizesoff = off;

         }
         s->strips = count;

         s->sstype = type;

         break;

     case TIFF_XRES:
     case TIFF_YRES:
         set_sar(s, tag, value, value2);
         break;

     case TIFF_TILE_BYTE_COUNTS:
     case TIFF_TILE_LENGTH:
     case TIFF_TILE_OFFSETS:
     case TIFF_TILE_WIDTH:
         av_log(s->avctx, AV_LOG_ERROR, "Tiled images are not supported\n");
         return AVERROR_PATCHWELCOME;
         break;

     case TIFF_PREDICTOR:

         s->predictor = value;

         break;

     case TIFF_PHOTOMETRIC:

         switch (value) {

         case TIFF_PHOTOMETRIC_WHITE_IS_ZERO:
         case TIFF_PHOTOMETRIC_BLACK_IS_ZERO:
         case TIFF_PHOTOMETRIC_RGB:
         case TIFF_PHOTOMETRIC_PALETTE:

         case TIFF_PHOTOMETRIC_YCBCR:

             s->photometric = value;

             break;

         case TIFF_PHOTOMETRIC_ALPHA_MASK:
         case TIFF_PHOTOMETRIC_SEPARATED:
         case TIFF_PHOTOMETRIC_CIE_LAB:
         case TIFF_PHOTOMETRIC_ICC_LAB:
         case TIFF_PHOTOMETRIC_ITU_LAB:
         case TIFF_PHOTOMETRIC_CFA:
         case TIFF_PHOTOMETRIC_LOG_L:
         case TIFF_PHOTOMETRIC_LOG_LUV:
         case TIFF_PHOTOMETRIC_LINEAR_RAW:
             avpriv_report_missing_feature(s->avctx,
                                           "PhotometricInterpretation 0x%04X",
                                           value);
             return AVERROR_PATCHWELCOME;

         default:

             av_log(s->avctx, AV_LOG_ERROR, "PhotometricInterpretation %u is "
                    "unknown\n", value);

             return AVERROR_INVALIDDATA;

         }
         break;

     case TIFF_FILL_ORDER:

         if (value < 1 || value > 2) {
             av_log(s->avctx, AV_LOG_ERROR,
                    "Unknown FillOrder value %d, trying default one\n", value);

             value = 1;
         }
         s->fill_order = value - 1;
         break;

     case TIFF_PAL: {
         GetByteContext pal_gb[3];

         off = type_sizes[type];

         if (count / 3 > 256 ||
             bytestream2_get_bytes_left(&s->gb) < count / 3 * off * 3)

             return AVERROR_INVALIDDATA;

         pal_gb[0] = pal_gb[1] = pal_gb[2] = s->gb;
         bytestream2_skip(&pal_gb[1], count / 3 * off);
         bytestream2_skip(&pal_gb[2], count / 3 * off * 2);

         off = (type_sizes[type] - 1) << 3;

         if (off > 31U) {
             av_log(s->avctx, AV_LOG_ERROR, "palette shift %d is out of range\n", off);
             return AVERROR_INVALIDDATA;
         }
 

         for (i = 0; i < count / 3; i++) {

             uint32_t p = 0xFF000000;

             p |= (ff_tget(&pal_gb[0], type, s->le) >> off) << 16;
             p |= (ff_tget(&pal_gb[1], type, s->le) >> off) << 8;
             p |=  ff_tget(&pal_gb[2], type, s->le) >> off;

             s->palette[i] = p;

         }

         s->palette_is_set = 1;

         break;

     }

     case TIFF_PLANAR:

         s->planar = value == 2;

         break;

     case TIFF_YCBCR_SUBSAMPLING:
         if (count != 2) {
             av_log(s->avctx, AV_LOG_ERROR, "subsample count invalid\n");
             return AVERROR_INVALIDDATA;
         }

         for (i = 0; i < count; i++) {

             s->subsampling[i] = ff_tget(&s->gb, type, s->le);

             if (s->subsampling[i] <= 0) {
                 av_log(s->avctx, AV_LOG_ERROR, "subsampling %d is invalid\n", s->subsampling[i]);

                 s->subsampling[i] = 1;

                 return AVERROR_INVALIDDATA;
             }
         }

         break;

     case TIFF_T4OPTIONS:

         if (s->compr == TIFF_G3)

             s->fax_opts = value;
         break;

     case TIFF_T6OPTIONS:

         if (s->compr == TIFF_G4)

             s->fax_opts = value;

         break;

 #define ADD_METADATA(count, name, sep)\

     if ((ret = add_metadata(count, type, name, sep, s, frame)) < 0) {\

         av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");\

         goto end;\

     }
     case TIFF_MODEL_PIXEL_SCALE:
         ADD_METADATA(count, "ModelPixelScaleTag", NULL);
         break;
     case TIFF_MODEL_TRANSFORMATION:
         ADD_METADATA(count, "ModelTransformationTag", NULL);
         break;
     case TIFF_MODEL_TIEPOINT:
         ADD_METADATA(count, "ModelTiepointTag", NULL);
         break;
     case TIFF_GEO_KEY_DIRECTORY:

         if (s->geotag_count) {
             avpriv_request_sample(s->avctx, "Multiple geo key directories\n");
             return AVERROR_INVALIDDATA;
         }

         ADD_METADATA(1, "GeoTIFF_Version", NULL);
         ADD_METADATA(2, "GeoTIFF_Key_Revision", ".");

         s->geotag_count   = ff_tget_short(&s->gb, s->le);

         if (s->geotag_count > count / 4 - 1) {
             s->geotag_count = count / 4 - 1;
             av_log(s->avctx, AV_LOG_WARNING, "GeoTIFF key directory buffer shorter than specified\n");
         }

         if (   bytestream2_get_bytes_left(&s->gb) < s->geotag_count * sizeof(int16_t) * 4
             || s->geotag_count == 0) {

             s->geotag_count = 0;

             return -1;

         }

         s->geotags = av_mallocz_array(s->geotag_count, sizeof(TiffGeoTag));

         if (!s->geotags) {
             av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");

             s->geotag_count = 0;

             goto end;

         }
         for (i = 0; i < s->geotag_count; i++) {

             s->geotags[i].key    = ff_tget_short(&s->gb, s->le);
             s->geotags[i].type   = ff_tget_short(&s->gb, s->le);
             s->geotags[i].count  = ff_tget_short(&s->gb, s->le);

 
             if (!s->geotags[i].type)

                 s->geotags[i].val  = get_geokey_val(s->geotags[i].key, ff_tget_short(&s->gb, s->le));

             else

                 s->geotags[i].offset = ff_tget_short(&s->gb, s->le);

         }
         break;
     case TIFF_GEO_DOUBLE_PARAMS:

         if (count >= INT_MAX / sizeof(int64_t))
             return AVERROR_INVALIDDATA;
         if (bytestream2_get_bytes_left(&s->gb) < count * sizeof(int64_t))
             return AVERROR_INVALIDDATA;

         dp = av_malloc_array(count, sizeof(double));

         if (!dp) {
             av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");

             goto end;

         }
         for (i = 0; i < count; i++)

             dp[i] = ff_tget_double(&s->gb, s->le);

         for (i = 0; i < s->geotag_count; i++) {
             if (s->geotags[i].type == TIFF_GEO_DOUBLE_PARAMS) {
                 if (s->geotags[i].count == 0
                     || s->geotags[i].offset + s->geotags[i].count > count) {
                     av_log(s->avctx, AV_LOG_WARNING, "Invalid GeoTIFF key %d\n", s->geotags[i].key);

                 } else if (s->geotags[i].val) {
                     av_log(s->avctx, AV_LOG_WARNING, "Duplicate GeoTIFF key %d\n", s->geotags[i].key);

                 } else {
                     char *ap = doubles2str(&dp[s->geotags[i].offset], s->geotags[i].count, ", ");
                     if (!ap) {
                         av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");
                         av_freep(&dp);
                         return AVERROR(ENOMEM);
                     }
                     s->geotags[i].val = ap;
                 }
             }
         }
         av_freep(&dp);
         break;
     case TIFF_GEO_ASCII_PARAMS:

         pos = bytestream2_tell(&s->gb);

         for (i = 0; i < s->geotag_count; i++) {
             if (s->geotags[i].type == TIFF_GEO_ASCII_PARAMS) {
                 if (s->geotags[i].count == 0
                     || s->geotags[i].offset +  s->geotags[i].count > count) {
                     av_log(s->avctx, AV_LOG_WARNING, "Invalid GeoTIFF key %d\n", s->geotags[i].key);
                 } else {

                     char *ap;
 
                     bytestream2_seek(&s->gb, pos + s->geotags[i].offset, SEEK_SET);
                     if (bytestream2_get_bytes_left(&s->gb) < s->geotags[i].count)

                         return AVERROR_INVALIDDATA;

                     if (s->geotags[i].val)
                         return AVERROR_INVALIDDATA;

                     ap = av_malloc(s->geotags[i].count);

                     if (!ap) {
                         av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");
                         return AVERROR(ENOMEM);
                     }

                     bytestream2_get_bufferu(&s->gb, ap, s->geotags[i].count);

                     ap[s->geotags[i].count - 1] = '\0'; //replace the "|" delimiter with a 0 byte
                     s->geotags[i].val = ap;
                 }
             }
         }
         break;

     case TIFF_ARTIST:
         ADD_METADATA(count, "artist", NULL);
         break;
     case TIFF_COPYRIGHT:
         ADD_METADATA(count, "copyright", NULL);
         break;
     case TIFF_DATE:
         ADD_METADATA(count, "date", NULL);
         break;
     case TIFF_DOCUMENT_NAME:
         ADD_METADATA(count, "document_name", NULL);
         break;
     case TIFF_HOST_COMPUTER:
         ADD_METADATA(count, "computer", NULL);
         break;
     case TIFF_IMAGE_DESCRIPTION:
         ADD_METADATA(count, "description", NULL);
         break;
     case TIFF_MAKE:
         ADD_METADATA(count, "make", NULL);
         break;
     case TIFF_MODEL:
         ADD_METADATA(count, "model", NULL);
         break;
     case TIFF_PAGE_NAME:
         ADD_METADATA(count, "page_name", NULL);
         break;
     case TIFF_PAGE_NUMBER:
         ADD_METADATA(count, "page_number", " / ");
         break;
     case TIFF_SOFTWARE_NAME:
         ADD_METADATA(count, "software", NULL);
         break;

     default:

         if (s->avctx->err_recognition & AV_EF_EXPLODE) {
             av_log(s->avctx, AV_LOG_ERROR,
                    "Unknown or unsupported tag %d/0X%0X\n",
                    tag, tag);
             return AVERROR_INVALIDDATA;
         }

     }

 end:

     if (s->bpp > 64U) {
         av_log(s->avctx, AV_LOG_ERROR,
                 "This format is not supported (bpp=%d, %d components)\n",
                 s->bpp, count);
         s->bpp = 0;
         return AVERROR_INVALIDDATA;
     }

     bytestream2_seek(&s->gb, start, SEEK_SET);

     return 0;
 }
 
 static int decode_frame(AVCodecContext *avctx,

                         void *data, int *got_frame, AVPacket *avpkt)

 {

     TiffContext *const s = avctx->priv_data;

     AVFrame *const p = data;

     ThreadFrame frame = { .f = data };

     unsigned off;

     int le, ret, plane, planes;

     int i, j, entries, stride;

     unsigned soff, ssize;

     uint8_t *dst;

     GetByteContext stripsizes;
     GetByteContext stripdata;
 
     bytestream2_init(&s->gb, avpkt->data, avpkt->size);

     // parse image header

     if ((ret = ff_tdecode_header(&s->gb, &le, &off))) {
         av_log(avctx, AV_LOG_ERROR, "Invalid TIFF header\n");
         return ret;
     } else if (off >= UINT_MAX - 14 || avpkt->size < off + 14) {
         av_log(avctx, AV_LOG_ERROR, "IFD offset is greater than image size\n");

         return AVERROR_INVALIDDATA;

     }

     s->le          = le;

     // TIFF_BPP is not a required tag and defaults to 1

     s->bppcount    = s->bpp = 1;

     s->photometric = TIFF_PHOTOMETRIC_NONE;
     s->compr       = TIFF_RAW;
     s->fill_order  = 0;

     free_geotags(s);
 

     // Reset these offsets so we can tell if they were set this frame
     s->stripsizesoff = s->strippos = 0;

     /* parse image file directory */

     bytestream2_seek(&s->gb, off, SEEK_SET);

     entries = ff_tget_short(&s->gb, le);

     if (bytestream2_get_bytes_left(&s->gb) < entries * 12)
         return AVERROR_INVALIDDATA;

     for (i = 0; i < entries; i++) {

         if ((ret = tiff_decode_tag(s, p)) < 0)

             return ret;

     }

 
     for (i = 0; i<s->geotag_count; i++) {
         const char *keyname = get_geokey_name(s->geotags[i].key);
         if (!keyname) {
             av_log(avctx, AV_LOG_WARNING, "Unknown or unsupported GeoTIFF key %d\n", s->geotags[i].key);
             continue;
         }
         if (get_geokey_type(s->geotags[i].key) != s->geotags[i].type) {
             av_log(avctx, AV_LOG_WARNING, "Type of GeoTIFF key %d is wrong\n", s->geotags[i].key);
             continue;
         }

         ret = av_dict_set(&p->metadata, keyname, s->geotags[i].val, 0);

         if (ret<0) {
             av_log(avctx, AV_LOG_ERROR, "Writing metadata with key '%s' failed\n", keyname);
             return ret;
         }
     }
 

     if (!s->strippos && !s->stripoff) {

         av_log(avctx, AV_LOG_ERROR, "Image data is missing\n");

         return AVERROR_INVALIDDATA;

     }
     /* now we have the data and may start decoding */

     if ((ret = init_image(s, &frame)) < 0)

         return ret;
 

     if (s->strips == 1 && !s->stripsize) {

         av_log(avctx, AV_LOG_WARNING, "Image data size missing\n");

         s->stripsize = avpkt->size - s->stripoff;

     }

 
     if (s->stripsizesoff) {

         if (s->stripsizesoff >= (unsigned)avpkt->size)

             return AVERROR_INVALIDDATA;

         bytestream2_init(&stripsizes, avpkt->data + s->stripsizesoff,
                          avpkt->size - s->stripsizesoff);

     }
     if (s->strippos) {

         if (s->strippos >= (unsigned)avpkt->size)

             return AVERROR_INVALIDDATA;

         bytestream2_init(&stripdata, avpkt->data + s->strippos,
                          avpkt->size - s->strippos);

     }
 

     if (s->rps <= 0 || s->rps % s->subsampling[1]) {

         av_log(avctx, AV_LOG_ERROR, "rps %d invalid\n", s->rps);
         return AVERROR_INVALIDDATA;
     }
 

     planes = s->planar ? s->bppcount : 1;
     for (plane = 0; plane < planes; plane++) {
         stride = p->linesize[plane];

         dst = p->data[plane];
         for (i = 0; i < s->height; i += s->rps) {

             if (i)
                 dst += s->rps * stride;

             if (s->stripsizesoff)

                 ssize = ff_tget(&stripsizes, s->sstype, le);

             else
                 ssize = s->stripsize;
 
             if (s->strippos)

                 soff = ff_tget(&stripdata, s->sot, le);

             else
                 soff = s->stripoff;
 
             if (soff > avpkt->size || ssize > avpkt->size - soff) {
                 av_log(avctx, AV_LOG_ERROR, "Invalid strip size/offset\n");
                 return AVERROR_INVALIDDATA;

             }

             if ((ret = tiff_unpack_strip(s, p, dst, stride, avpkt->data + soff, ssize, i,

                                          FFMIN(s->rps, s->height - i))) < 0) {
                 if (avctx->err_recognition & AV_EF_EXPLODE)
                     return ret;
                 break;

             }

         }

         if (s->predictor == 2) {

             if (s->photometric == TIFF_PHOTOMETRIC_YCBCR) {
                 av_log(s->avctx, AV_LOG_ERROR, "predictor == 2 with YUV is unsupported");
                 return AVERROR_PATCHWELCOME;

             }

             dst   = p->data[plane];
             soff  = s->bpp >> 3;

             if (s->planar)
                 soff  = FFMAX(soff / s->bppcount, 1);

             ssize = s->width * soff;
             if (s->avctx->pix_fmt == AV_PIX_FMT_RGB48LE ||

                 s->avctx->pix_fmt == AV_PIX_FMT_RGBA64LE ||

                 s->avctx->pix_fmt == AV_PIX_FMT_GRAY16LE ||
                 s->avctx->pix_fmt == AV_PIX_FMT_YA16LE ||

                 s->avctx->pix_fmt == AV_PIX_FMT_GBRP16LE ||
                 s->avctx->pix_fmt == AV_PIX_FMT_GBRAP16LE) {

                 for (i = 0; i < s->height; i++) {
                     for (j = soff; j < ssize; j += 2)
                         AV_WL16(dst + j, AV_RL16(dst + j) + AV_RL16(dst + j - soff));
                     dst += stride;
                 }
             } else if (s->avctx->pix_fmt == AV_PIX_FMT_RGB48BE ||

                        s->avctx->pix_fmt == AV_PIX_FMT_RGBA64BE ||

                        s->avctx->pix_fmt == AV_PIX_FMT_GRAY16BE ||
                        s->avctx->pix_fmt == AV_PIX_FMT_YA16BE ||

                        s->avctx->pix_fmt == AV_PIX_FMT_GBRP16BE ||
                        s->avctx->pix_fmt == AV_PIX_FMT_GBRAP16BE) {

                 for (i = 0; i < s->height; i++) {
                     for (j = soff; j < ssize; j += 2)
                         AV_WB16(dst + j, AV_RB16(dst + j) + AV_RB16(dst + j - soff));
                     dst += stride;
                 }
             } else {
                 for (i = 0; i < s->height; i++) {
                     for (j = soff; j < ssize; j++)
                         dst[j] += dst[j - soff];
                     dst += stride;
                 }

             }

         }
 
         if (s->photometric == TIFF_PHOTOMETRIC_WHITE_IS_ZERO) {

             int c = (s->avctx->pix_fmt == AV_PIX_FMT_PAL8 ? (1<<s->bpp) - 1 : 255);

             dst = p->data[plane];

             for (i = 0; i < s->height; i++) {

                 for (j = 0; j < stride; j++)

                     dst[j] = c - dst[j];

                 dst += stride;
             }

         }

     }

     if (s->planar && s->bppcount > 2) {

         FFSWAP(uint8_t*, p->data[0],     p->data[2]);
         FFSWAP(int,      p->linesize[0], p->linesize[2]);
         FFSWAP(uint8_t*, p->data[0],     p->data[1]);
         FFSWAP(int,      p->linesize[0], p->linesize[1]);
     }
 

     *got_frame = 1;

     return avpkt->size;

 }
 

 static av_cold int tiff_init(AVCodecContext *avctx)
 {

     TiffContext *s = avctx->priv_data;
 

     s->width  = 0;

     s->height = 0;

     s->subsampling[0] =
     s->subsampling[1] = 1;

     s->avctx  = avctx;

     ff_lzw_decode_open(&s->lzw);

     ff_ccitt_unpack_init();

 
     return 0;
 }
 

 static av_cold int tiff_end(AVCodecContext *avctx)

 {

     TiffContext *const s = avctx->priv_data;

     free_geotags(s);
 

     ff_lzw_decode_close(&s->lzw);

     av_freep(&s->deinvert_buf);

     s->deinvert_buf_size = 0;

     av_freep(&s->fax_buffer);
     s->fax_buffer_size = 0;

     return 0;
 }
 

 AVCodec ff_tiff_decoder = {

     .name           = "tiff",

     .long_name      = NULL_IF_CONFIG_SMALL("TIFF image"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_TIFF,

     .priv_data_size = sizeof(TiffContext),
     .init           = tiff_init,
     .close          = tiff_end,
     .decode         = decode_frame,

     .init_thread_copy = ONLY_IF_THREADS_ENABLED(tiff_init),

     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,

 };