/*
  * MJPEG encoder

  * Copyright (c) 2000, 2001 Fabrice Bellard

  * Copyright (c) 2003 Alex Beregszaszi
  * Copyright (c) 2003-2004 Michael Niedermayer
  *

  * Support for external huffman table, various fixes (AVID workaround),
  * aspecting, new decode_frame mechanism and apple mjpeg-b support
  *                                  by Alex Beregszaszi
  *

  * 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

  * MJPEG encoder.
  */
 
 //#define DEBUG
 #include <assert.h>
 
 #include "avcodec.h"
 #include "dsputil.h"
 #include "mpegvideo.h"
 #include "mjpeg.h"

 #include "mjpegenc.h"

 
 /* use two quantizer tables (one for luminance and one for chrominance) */
 /* not yet working */
 #undef TWOMATRIXES
 
 

 av_cold int ff_mjpeg_encode_init(MpegEncContext *s)

 {
     MJpegContext *m;
 
     m = av_malloc(sizeof(MJpegContext));
     if (!m)
         return -1;
 
     s->min_qcoeff=-1023;
     s->max_qcoeff= 1023;
 
     /* build all the huffman tables */

     ff_mjpeg_build_huffman_codes(m->huff_size_dc_luminance,
                                  m->huff_code_dc_luminance,
                                  ff_mjpeg_bits_dc_luminance,

                                  ff_mjpeg_val_dc);

     ff_mjpeg_build_huffman_codes(m->huff_size_dc_chrominance,
                                  m->huff_code_dc_chrominance,
                                  ff_mjpeg_bits_dc_chrominance,

                                  ff_mjpeg_val_dc);

     ff_mjpeg_build_huffman_codes(m->huff_size_ac_luminance,
                                  m->huff_code_ac_luminance,
                                  ff_mjpeg_bits_ac_luminance,
                                  ff_mjpeg_val_ac_luminance);
     ff_mjpeg_build_huffman_codes(m->huff_size_ac_chrominance,
                                  m->huff_code_ac_chrominance,
                                  ff_mjpeg_bits_ac_chrominance,
                                  ff_mjpeg_val_ac_chrominance);

 
     s->mjpeg_ctx = m;
     return 0;
 }
 

 void ff_mjpeg_encode_close(MpegEncContext *s)

 {
     av_free(s->mjpeg_ctx);
 }
 
 /* table_class: 0 = DC coef, 1 = AC coefs */
 static int put_huffman_table(MpegEncContext *s, int table_class, int table_id,
                              const uint8_t *bits_table, const uint8_t *value_table)
 {
     PutBitContext *p = &s->pb;
     int n, i;
 
     put_bits(p, 4, table_class);
     put_bits(p, 4, table_id);
 
     n = 0;
     for(i=1;i<=16;i++) {
         n += bits_table[i];
         put_bits(p, 8, bits_table[i]);
     }
 
     for(i=0;i<n;i++)
         put_bits(p, 8, value_table[i]);
 
     return n + 17;
 }
 
 static void jpeg_table_header(MpegEncContext *s)
 {
     PutBitContext *p = &s->pb;
     int i, j, size;
     uint8_t *ptr;
 
     /* quant matrixes */
     put_marker(p, DQT);
 #ifdef TWOMATRIXES
     put_bits(p, 16, 2 + 2 * (1 + 64));
 #else
     put_bits(p, 16, 2 + 1 * (1 + 64));
 #endif
     put_bits(p, 4, 0); /* 8 bit precision */
     put_bits(p, 4, 0); /* table 0 */
     for(i=0;i<64;i++) {
         j = s->intra_scantable.permutated[i];
         put_bits(p, 8, s->intra_matrix[j]);
     }
 #ifdef TWOMATRIXES
     put_bits(p, 4, 0); /* 8 bit precision */
     put_bits(p, 4, 1); /* table 1 */
     for(i=0;i<64;i++) {
         j = s->intra_scantable.permutated[i];
         put_bits(p, 8, s->chroma_intra_matrix[j]);
     }
 #endif
 
     /* huffman table */
     put_marker(p, DHT);
     flush_put_bits(p);

     ptr = put_bits_ptr(p);

     put_bits(p, 16, 0); /* patched later */
     size = 2;

     size += put_huffman_table(s, 0, 0, ff_mjpeg_bits_dc_luminance,

                               ff_mjpeg_val_dc);

     size += put_huffman_table(s, 0, 1, ff_mjpeg_bits_dc_chrominance,

                               ff_mjpeg_val_dc);

 
     size += put_huffman_table(s, 1, 0, ff_mjpeg_bits_ac_luminance,
                               ff_mjpeg_val_ac_luminance);
     size += put_huffman_table(s, 1, 1, ff_mjpeg_bits_ac_chrominance,
                               ff_mjpeg_val_ac_chrominance);

     AV_WB16(ptr, size);

 }
 
 static void jpeg_put_comments(MpegEncContext *s)
 {
     PutBitContext *p = &s->pb;
     int size;
     uint8_t *ptr;
 

     if (s->avctx->sample_aspect_ratio.num /* && !lossless */)

     {
     /* JFIF header */
     put_marker(p, APP0);
     put_bits(p, 16, 16);
     ff_put_string(p, "JFIF", 1); /* this puts the trailing zero-byte too */

     put_bits(p, 16, 0x0102); /* v 1.02 */

     put_bits(p, 8, 0); /* units type: 0 - aspect ratio */
     put_bits(p, 16, s->avctx->sample_aspect_ratio.num);
     put_bits(p, 16, s->avctx->sample_aspect_ratio.den);
     put_bits(p, 8, 0); /* thumbnail width */
     put_bits(p, 8, 0); /* thumbnail height */
     }
 
     /* comment */
     if(!(s->flags & CODEC_FLAG_BITEXACT)){
         put_marker(p, COM);
         flush_put_bits(p);

         ptr = put_bits_ptr(p);

         put_bits(p, 16, 0); /* patched later */
         ff_put_string(p, LIBAVCODEC_IDENT, 1);
         size = strlen(LIBAVCODEC_IDENT)+3;

         AV_WB16(ptr, size);

     }
 
     if(  s->avctx->pix_fmt == PIX_FMT_YUV420P
        ||s->avctx->pix_fmt == PIX_FMT_YUV422P
        ||s->avctx->pix_fmt == PIX_FMT_YUV444P){
         put_marker(p, COM);
         flush_put_bits(p);

         ptr = put_bits_ptr(p);

         put_bits(p, 16, 0); /* patched later */
         ff_put_string(p, "CS=ITU601", 1);
         size = strlen("CS=ITU601")+3;

         AV_WB16(ptr, size);

     }
 }
 

 void ff_mjpeg_encode_picture_header(MpegEncContext *s)

 {
     const int lossless= s->avctx->codec_id != CODEC_ID_MJPEG;
 
     put_marker(&s->pb, SOI);
 

     // hack for AMV mjpeg format
     if(s->avctx->codec_id == CODEC_ID_AMV) return;
 

     jpeg_put_comments(s);
 
     jpeg_table_header(s);
 
     switch(s->avctx->codec_id){
     case CODEC_ID_MJPEG:  put_marker(&s->pb, SOF0 ); break;
     case CODEC_ID_LJPEG:  put_marker(&s->pb, SOF3 ); break;
     default: assert(0);
     }
 
     put_bits(&s->pb, 16, 17);

     if(lossless && s->avctx->pix_fmt == PIX_FMT_BGRA)

         put_bits(&s->pb, 8, 9); /* 9 bits/component RCT */
     else
         put_bits(&s->pb, 8, 8); /* 8 bits/component */
     put_bits(&s->pb, 16, s->height);
     put_bits(&s->pb, 16, s->width);
     put_bits(&s->pb, 8, 3); /* 3 components */
 
     /* Y component */
     put_bits(&s->pb, 8, 1); /* component number */
     put_bits(&s->pb, 4, s->mjpeg_hsample[0]); /* H factor */
     put_bits(&s->pb, 4, s->mjpeg_vsample[0]); /* V factor */
     put_bits(&s->pb, 8, 0); /* select matrix */
 
     /* Cb component */
     put_bits(&s->pb, 8, 2); /* component number */
     put_bits(&s->pb, 4, s->mjpeg_hsample[1]); /* H factor */
     put_bits(&s->pb, 4, s->mjpeg_vsample[1]); /* V factor */
 #ifdef TWOMATRIXES
     put_bits(&s->pb, 8, lossless ? 0 : 1); /* select matrix */
 #else
     put_bits(&s->pb, 8, 0); /* select matrix */
 #endif
 
     /* Cr component */
     put_bits(&s->pb, 8, 3); /* component number */
     put_bits(&s->pb, 4, s->mjpeg_hsample[2]); /* H factor */
     put_bits(&s->pb, 4, s->mjpeg_vsample[2]); /* V factor */
 #ifdef TWOMATRIXES
     put_bits(&s->pb, 8, lossless ? 0 : 1); /* select matrix */
 #else
     put_bits(&s->pb, 8, 0); /* select matrix */
 #endif
 
     /* scan header */
     put_marker(&s->pb, SOS);
     put_bits(&s->pb, 16, 12); /* length */
     put_bits(&s->pb, 8, 3); /* 3 components */
 
     /* Y component */
     put_bits(&s->pb, 8, 1); /* index */
     put_bits(&s->pb, 4, 0); /* DC huffman table index */
     put_bits(&s->pb, 4, 0); /* AC huffman table index */
 
     /* Cb component */
     put_bits(&s->pb, 8, 2); /* index */
     put_bits(&s->pb, 4, 1); /* DC huffman table index */
     put_bits(&s->pb, 4, lossless ? 0 : 1); /* AC huffman table index */
 
     /* Cr component */
     put_bits(&s->pb, 8, 3); /* index */
     put_bits(&s->pb, 4, 1); /* DC huffman table index */
     put_bits(&s->pb, 4, lossless ? 0 : 1); /* AC huffman table index */
 
     put_bits(&s->pb, 8, lossless ? s->avctx->prediction_method+1 : 0); /* Ss (not used) */
 
     switch(s->avctx->codec_id){
     case CODEC_ID_MJPEG:  put_bits(&s->pb, 8, 63); break; /* Se (not used) */
     case CODEC_ID_LJPEG:  put_bits(&s->pb, 8,  0); break; /* not used */
     default: assert(0);
     }
 
     put_bits(&s->pb, 8, 0); /* Ah/Al (not used) */
 }
 
 static void escape_FF(MpegEncContext *s, int start)
 {
     int size= put_bits_count(&s->pb) - start*8;
     int i, ff_count;
     uint8_t *buf= s->pb.buf + start;
     int align= (-(size_t)(buf))&3;
 
     assert((size&7) == 0);
     size >>= 3;
 
     ff_count=0;
     for(i=0; i<size && i<align; i++){
         if(buf[i]==0xFF) ff_count++;
     }
     for(; i<size-15; i+=16){
         int acc, v;
 
         v= *(uint32_t*)(&buf[i]);
         acc= (((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
         v= *(uint32_t*)(&buf[i+4]);
         acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
         v= *(uint32_t*)(&buf[i+8]);
         acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
         v= *(uint32_t*)(&buf[i+12]);
         acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
 
         acc>>=4;
         acc+= (acc>>16);
         acc+= (acc>>8);
         ff_count+= acc&0xFF;
     }
     for(; i<size; i++){
         if(buf[i]==0xFF) ff_count++;
     }
 
     if(ff_count==0) return;
 
     flush_put_bits(&s->pb);

     skip_put_bytes(&s->pb, ff_count);

 
     for(i=size-1; ff_count; i--){
         int v= buf[i];
 
         if(v==0xFF){
 //printf("%d %d\n", i, ff_count);
             buf[i+ff_count]= 0;
             ff_count--;
         }
 
         buf[i+ff_count]= v;
     }
 }
 

 void ff_mjpeg_encode_stuffing(PutBitContext * pbc)

 {
     int length;
     length= (-put_bits_count(pbc))&7;
     if(length) put_bits(pbc, length, (1<<length)-1);
 }
 

 void ff_mjpeg_encode_picture_trailer(MpegEncContext *s)

 {

     ff_mjpeg_encode_stuffing(&s->pb);

     flush_put_bits(&s->pb);
 
     assert((s->header_bits&7)==0);
 
     escape_FF(s, s->header_bits>>3);
 
     put_marker(&s->pb, EOI);
 }
 

 void ff_mjpeg_encode_dc(MpegEncContext *s, int val,
                         uint8_t *huff_size, uint16_t *huff_code)

 {
     int mant, nbits;
 
     if (val == 0) {
         put_bits(&s->pb, huff_size[0], huff_code[0]);
     } else {
         mant = val;
         if (val < 0) {
             val = -val;
             mant--;
         }
 
         nbits= av_log2_16bit(val) + 1;
 
         put_bits(&s->pb, huff_size[nbits], huff_code[nbits]);
 

         put_sbits(&s->pb, nbits, mant);

     }
 }
 
 static void encode_block(MpegEncContext *s, DCTELEM *block, int n)
 {
     int mant, nbits, code, i, j;
     int component, dc, run, last_index, val;
     MJpegContext *m = s->mjpeg_ctx;
     uint8_t *huff_size_ac;
     uint16_t *huff_code_ac;
 
     /* DC coef */
     component = (n <= 3 ? 0 : (n&1) + 1);
     dc = block[0]; /* overflow is impossible */
     val = dc - s->last_dc[component];
     if (n < 4) {

         ff_mjpeg_encode_dc(s, val, m->huff_size_dc_luminance, m->huff_code_dc_luminance);

         huff_size_ac = m->huff_size_ac_luminance;
         huff_code_ac = m->huff_code_ac_luminance;
     } else {

         ff_mjpeg_encode_dc(s, val, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);

         huff_size_ac = m->huff_size_ac_chrominance;
         huff_code_ac = m->huff_code_ac_chrominance;
     }
     s->last_dc[component] = dc;
 
     /* AC coefs */
 
     run = 0;
     last_index = s->block_last_index[n];
     for(i=1;i<=last_index;i++) {
         j = s->intra_scantable.permutated[i];
         val = block[j];
         if (val == 0) {
             run++;
         } else {
             while (run >= 16) {
                 put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);
                 run -= 16;
             }
             mant = val;
             if (val < 0) {
                 val = -val;
                 mant--;
             }
 
             nbits= av_log2(val) + 1;
             code = (run << 4) | nbits;
 
             put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);
 

             put_sbits(&s->pb, nbits, mant);

             run = 0;
         }
     }
 
     /* output EOB only if not already 64 values */
     if (last_index < 63 || run != 0)
         put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
 }
 

 void ff_mjpeg_encode_mb(MpegEncContext *s, DCTELEM block[6][64])

 {
     int i;
     for(i=0;i<5;i++) {
         encode_block(s, block[i], i);
     }
     if (s->chroma_format == CHROMA_420) {
         encode_block(s, block[5], 5);
     } else {
         encode_block(s, block[6], 6);
         encode_block(s, block[5], 5);
         encode_block(s, block[7], 7);
     }

 
     s->i_tex_bits += get_bits_diff(s);

 }

 // maximum over s->mjpeg_vsample[i]
 #define V_MAX 2
 static int amv_encode_picture(AVCodecContext *avctx,
                        unsigned char *buf, int buf_size, void *data)
 {
 
     AVFrame* pic=data;
     MpegEncContext *s = avctx->priv_data;
     int i;
 
     //CODEC_FLAG_EMU_EDGE have to be cleared
     if(s->avctx->flags & CODEC_FLAG_EMU_EDGE)
         return -1;
 
     //picture should be flipped upside-down
     for(i=0; i < 3; i++) {
         pic->data[i] += (pic->linesize[i] * (s->mjpeg_vsample[i] * (8 * s->mb_height -((s->height/V_MAX)&7)) - 1 ));
         pic->linesize[i] *= -1;
     }
     return MPV_encode_picture(avctx,buf, buf_size, pic);
 }
 

 AVCodec ff_mjpeg_encoder = {

     .name           = "mjpeg",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = CODEC_ID_MJPEG,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = MPV_encode_init,
     .encode         = MPV_encode_picture,
     .close          = MPV_encode_end,

     .pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUVJ420P, PIX_FMT_YUVJ422P, PIX_FMT_NONE},

     .long_name= NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),

 };

 
 AVCodec ff_amv_encoder = {

     .name           = "amv",
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = CODEC_ID_AMV,
     .priv_data_size = sizeof(MpegEncContext),
     .init           = MPV_encode_init,
     .encode         = amv_encode_picture,
     .close          = MPV_encode_end,

     .pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUVJ420P, PIX_FMT_YUVJ422P, PIX_FMT_NONE},

     .long_name      = NULL_IF_CONFIG_SMALL("AMV Video"),

 };