/*
  * NuppelVideo decoder
  * Copyright (c) 2006 Reimar Doeffinger
  *

  * 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
  */

 #include <stdio.h>
 #include <stdlib.h>

 #include <limits.h>

 #include "libavutil/bswap.h"

 #include "libavutil/common.h"

 #include "libavutil/lzo.h"

 #include "libavutil/imgutils.h"

 #include "avcodec.h"

 #include "internal.h"

 #include "rtjpeg.h"
 
 typedef struct {
     AVFrame pic;

     int codec_frameheader;

     int quality;

     int width, height;
     unsigned int decomp_size;

     unsigned char *decomp_buf;

     uint32_t lq[64], cq[64];
     RTJpegContext rtj;
     DSPContext dsp;
 } NuvContext;
 

 static const uint8_t fallback_lquant[] = {
     16,  11,  10,  16,  24,  40,  51,  61,
     12,  12,  14,  19,  26,  58,  60,  55,
     14,  13,  16,  24,  40,  57,  69,  56,
     14,  17,  22,  29,  51,  87,  80,  62,
     18,  22,  37,  56,  68, 109, 103,  77,
     24,  35,  55,  64,  81, 104, 113,  92,
     49,  64,  78,  87, 103, 121, 120, 101,
     72,  92,  95,  98, 112, 100, 103,  99
 };
 
 static const uint8_t fallback_cquant[] = {
     17, 18, 24, 47, 99, 99, 99, 99,
     18, 21, 26, 66, 99, 99, 99, 99,
     24, 26, 56, 99, 99, 99, 99, 99,
     47, 66, 99, 99, 99, 99, 99, 99,
     99, 99, 99, 99, 99, 99, 99, 99,
     99, 99, 99, 99, 99, 99, 99, 99,
     99, 99, 99, 99, 99, 99, 99, 99,
     99, 99, 99, 99, 99, 99, 99, 99
 };
 

 /**

  * @brief copy frame data from buffer to AVFrame, handling stride.
  * @param f destination AVFrame
  * @param src source buffer, does not use any line-stride
  * @param width width of the video frame
  * @param height height of the video frame

  */

 static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
 {

     AVPicture pic;

     avpicture_fill(&pic, src, AV_PIX_FMT_YUV420P, width, height);
     av_picture_copy((AVPicture *)f, &pic, AV_PIX_FMT_YUV420P, width, height);

 }
 
 /**

  * @brief extract quantization tables from codec data into our context

  */

 static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf,
                      int size)
 {

     int i;
     if (size < 2 * 64 * 4) {
         av_log(avctx, AV_LOG_ERROR, "insufficient rtjpeg quant data\n");

         return AVERROR_INVALIDDATA;

     }
     for (i = 0; i < 64; i++, buf += 4)

         c->lq[i] = AV_RL32(buf);

     for (i = 0; i < 64; i++, buf += 4)

         c->cq[i] = AV_RL32(buf);

     return 0;
 }
 

 /**

  * @brief set quantization tables from a quality value

  */

 static void get_quant_quality(NuvContext *c, int quality)
 {

     int i;

     quality = FFMAX(quality, 1);

     for (i = 0; i < 64; i++) {
         c->lq[i] = (fallback_lquant[i] << 7) / quality;
         c->cq[i] = (fallback_cquant[i] << 7) / quality;
     }
 }
 

 static int codec_reinit(AVCodecContext *avctx, int width, int height,
                         int quality)
 {

     NuvContext *c = avctx->priv_data;

     int ret;
 

     width  = FFALIGN(width,  2);
     height = FFALIGN(height, 2);

     if (quality >= 0)
         get_quant_quality(c, quality);
     if (width != c->width || height != c->height) {

         // also reserve space for a possible additional header
         int buf_size = 24 + height * width * 3 / 2 + AV_LZO_OUTPUT_PADDING;

         if (buf_size > INT_MAX/8)

             return -1;

         if ((ret = av_image_check_size(height, width, 0, avctx)) < 0)
             return ret;

         avctx->width  = c->width  = width;

         avctx->height = c->height = height;

         av_fast_malloc(&c->decomp_buf, &c->decomp_size,

                        buf_size);

         if (!c->decomp_buf) {

             av_log(avctx, AV_LOG_ERROR,
                    "Can't allocate decompression buffer.\n");

             return AVERROR(ENOMEM);

         }

         ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
                               c->lq, c->cq);

         return 1;

     } else if (quality != c->quality)

         ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
                               c->lq, c->cq);
 

     return 0;

 }
 

 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

                         AVPacket *avpkt)
 {

     const uint8_t *buf = avpkt->data;

     int buf_size       = avpkt->size;
     NuvContext *c      = avctx->priv_data;
     AVFrame *picture   = data;
     int orig_size      = buf_size;

     int keyframe;

     int size_change = 0;

     int result, init_frame = !avctx->frame_number;

     enum {
         NUV_UNCOMPRESSED  = '0',
         NUV_RTJPEG        = '1',
         NUV_RTJPEG_IN_LZO = '2',
         NUV_LZO           = '3',
         NUV_BLACK         = 'N',
         NUV_COPY_LAST     = 'L'
     } comptype;

 
     if (buf_size < 12) {
         av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");

         return AVERROR_INVALIDDATA;

     }
 
     // codec data (rtjpeg quant tables)
     if (buf[0] == 'D' && buf[1] == 'R') {
         int ret;
         // skip rest of the frameheader.

         buf       = &buf[12];

         buf_size -= 12;

         ret       = get_quant(avctx, c, buf, buf_size);

         if (ret < 0)
             return ret;

         ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height, c->lq,
                               c->cq);

         return orig_size;
     }
 

     if (buf_size < 12 || buf[0] != 'V') {

         av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");

         return AVERROR_INVALIDDATA;

     }
     comptype = buf[1];

     switch (comptype) {

     case NUV_RTJPEG_IN_LZO:
     case NUV_RTJPEG:
         keyframe = !buf[2];
         break;
     case NUV_COPY_LAST:
         keyframe = 0;
         break;
     default:
         keyframe = 1;
         break;

     }

 retry:

     // skip rest of the frameheader.

     buf       = &buf[12];

     buf_size -= 12;

     if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {

         int outlen = c->decomp_size - AV_LZO_OUTPUT_PADDING, inlen = buf_size;

         if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen))

             av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");

         buf      = c->decomp_buf;

         buf_size = c->decomp_size - AV_LZO_OUTPUT_PADDING - outlen;

     }

     if (c->codec_frameheader) {

         int w, h, q;

         if (buf_size < RTJPEG_HEADER_SIZE) {

             av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");
             return AVERROR_INVALIDDATA;
         }
         // There seem to exist two variants of this header: one starts with 'V'
         // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,
         // 1 byte header size (== 12), 1 byte version (== 0)
         if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {
             av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");

             return AVERROR_INVALIDDATA;

         }

         w = AV_RL16(&buf[6]);
         h = AV_RL16(&buf[8]);
         q = buf[10];

         if ((result = codec_reinit(avctx, w, h, q)) < 0)
             return result;

         if (result) {

             buf = avpkt->data;
             buf_size = avpkt->size;
             size_change = 1;
             goto retry;
         }

         buf       = &buf[RTJPEG_HEADER_SIZE];

         buf_size -= RTJPEG_HEADER_SIZE;

     }

     if (size_change || keyframe) {

         av_frame_unref(&c->pic);

         init_frame = 1;
     }

     if ((result = ff_reget_buffer(avctx, &c->pic)) < 0)

         return result;

     if (init_frame) {
         memset(c->pic.data[0], 0,    avctx->height * c->pic.linesize[0]);
         memset(c->pic.data[1], 0x80, avctx->height * c->pic.linesize[1] / 2);
         memset(c->pic.data[2], 0x80, avctx->height * c->pic.linesize[2] / 2);
     }

     c->pic.pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;

     c->pic.key_frame = keyframe;

     // decompress/copy/whatever data
     switch (comptype) {

     case NUV_LZO:
     case NUV_UNCOMPRESSED: {
         int height = c->height;
         if (buf_size < c->width * height * 3 / 2) {
             av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");
             height = buf_size / c->width / 3 * 2;

         }

         if(height > 0)
             copy_frame(&c->pic, buf, c->width, height);

         break;
     }
     case NUV_RTJPEG_IN_LZO:
     case NUV_RTJPEG:
         ff_rtjpeg_decode_frame_yuv420(&c->rtj, &c->pic, buf, buf_size);
         break;
     case NUV_BLACK:
         memset(c->pic.data[0], 0, c->width * c->height);
         memset(c->pic.data[1], 128, c->width * c->height / 4);
         memset(c->pic.data[2], 128, c->width * c->height / 4);
         break;
     case NUV_COPY_LAST:
         /* nothing more to do here */
         break;
     default:
         av_log(avctx, AV_LOG_ERROR, "unknown compression\n");

         return AVERROR_INVALIDDATA;

     }
 

     if ((result = av_frame_ref(picture, &c->pic)) < 0)
         return result;
 

     *got_frame = 1;

     return orig_size;
 }
 

 static av_cold int decode_init(AVCodecContext *avctx)
 {
     NuvContext *c  = avctx->priv_data;

     int ret;
 

     avctx->pix_fmt = AV_PIX_FMT_YUV420P;

     c->pic.data[0] = NULL;

     c->decomp_buf  = NULL;
     c->quality     = -1;
     c->width       = 0;
     c->height      = 0;
 

     c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');

     if (avctx->extradata_size)
         get_quant(avctx, c, avctx->extradata, avctx->extradata_size);

     ff_dsputil_init(&c->dsp, avctx);

     if ((ret = codec_reinit(avctx, avctx->width, avctx->height, -1)) < 0)
         return ret;

     return 0;
 }
 

 static av_cold int decode_end(AVCodecContext *avctx)
 {

     NuvContext *c = avctx->priv_data;

     av_freep(&c->decomp_buf);

     av_frame_unref(&c->pic);

     return 0;
 }
 

 AVCodec ff_nuv_decoder = {

     .name           = "nuv",
     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_NUV,

     .priv_data_size = sizeof(NuvContext),
     .init           = decode_init,
     .close          = decode_end,
     .decode         = decode_frame,
     .capabilities   = CODEC_CAP_DR1,

     .long_name      = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),

 };