text: /*
   * lossless JPEG shared bits
   * Copyright (c) 2000, 2001 Fabrice Bellard
   * Copyright (c) 2003 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
   */
  
  #include <stdint.h>
  #include <string.h>
  
  #include "libavutil/common.h"
  #include "libavutil/pixdesc.h"
  #include "libavutil/pixfmt.h"
  
  #include "avcodec.h"
  #include "idctdsp.h"
  #include "jpegtables.h"
  #include "put_bits.h"
  #include "mjpegenc.h"
  #include "mjpegenc_common.h"
  #include "mjpeg.h"
  
  /* table_class: 0 = DC coef, 1 = AC coefs */
  static int put_huffman_table(PutBitContext *p, int table_class, int table_id,
                               const uint8_t *bits_table, const uint8_t *value_table)
  {
      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(AVCodecContext *avctx, PutBitContext *p,
                                ScanTable *intra_scantable,
                                uint16_t luma_intra_matrix[64],
                                uint16_t chroma_intra_matrix[64],
                                int hsample[3])
  {
      int i, j, size;
      uint8_t *ptr;
  
      if (avctx->codec_id != AV_CODEC_ID_LJPEG) {
          int matrix_count = 1 + !!memcmp(luma_intra_matrix,
                                          chroma_intra_matrix,
                                          sizeof(luma_intra_matrix[0]) * 64);
      /* quant matrixes */
      put_marker(p, DQT);
      put_bits(p, 16, 2 + matrix_count * (1 + 64));
      put_bits(p, 4, 0); /* 8 bit precision */
      put_bits(p, 4, 0); /* table 0 */
      for(i=0;i<64;i++) {
          j = intra_scantable->permutated[i];
          put_bits(p, 8, luma_intra_matrix[j]);
      }
  
          if (matrix_count > 1) {
              put_bits(p, 4, 0); /* 8 bit precision */
              put_bits(p, 4, 1); /* table 1 */
              for(i=0;i<64;i++) {
                  j = intra_scantable->permutated[i];
                  put_bits(p, 8, chroma_intra_matrix[j]);
              }
          }
      }
  
      if(avctx->active_thread_type & FF_THREAD_SLICE){
          put_marker(p, DRI);
          put_bits(p, 16, 4);
          put_bits(p, 16, (avctx->width-1)/(8*hsample[0]) + 1);
      }
  
      /* 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(p, 0, 0, avpriv_mjpeg_bits_dc_luminance,
                                avpriv_mjpeg_val_dc);
      size += put_huffman_table(p, 0, 1, avpriv_mjpeg_bits_dc_chrominance,
                                avpriv_mjpeg_val_dc);
  
      size += put_huffman_table(p, 1, 0, avpriv_mjpeg_bits_ac_luminance,
                                avpriv_mjpeg_val_ac_luminance);
      size += put_huffman_table(p, 1, 1, avpriv_mjpeg_bits_ac_chrominance,
                                avpriv_mjpeg_val_ac_chrominance);
      AV_WB16(ptr, size);
  }
  
  static void jpeg_put_comments(AVCodecContext *avctx, PutBitContext *p)
  {
      int size;
      uint8_t *ptr;
  
      if (avctx->sample_aspect_ratio.num > 0 && avctx->sample_aspect_ratio.den > 0) {
          /* JFIF header */
          put_marker(p, APP0);
          put_bits(p, 16, 16);
          avpriv_put_string(p, "JFIF", 1); /* this puts the trailing zero-byte too */
          /* The most significant byte is used for major revisions, the least
           * significant byte for minor revisions. Version 1.02 is the current
           * released revision. */
          put_bits(p, 16, 0x0102);
          put_bits(p,  8, 0);              /* units type: 0 - aspect ratio */
          put_bits(p, 16, avctx->sample_aspect_ratio.num);
          put_bits(p, 16, avctx->sample_aspect_ratio.den);
          put_bits(p, 8, 0); /* thumbnail width */
          put_bits(p, 8, 0); /* thumbnail height */
      }
  
      /* comment */
      if (!(avctx->flags & AV_CODEC_FLAG_BITEXACT)) {
          put_marker(p, COM);
          flush_put_bits(p);
          ptr = put_bits_ptr(p);
          put_bits(p, 16, 0); /* patched later */
          avpriv_put_string(p, LIBAVCODEC_IDENT, 1);
          size = strlen(LIBAVCODEC_IDENT)+3;
          AV_WB16(ptr, size);
      }
  
      if (((avctx->pix_fmt == AV_PIX_FMT_YUV420P ||
            avctx->pix_fmt == AV_PIX_FMT_YUV422P ||
            avctx->pix_fmt == AV_PIX_FMT_YUV444P) && avctx->color_range != AVCOL_RANGE_JPEG)
          || avctx->color_range == AVCOL_RANGE_MPEG) {
          put_marker(p, COM);
          flush_put_bits(p);
          ptr = put_bits_ptr(p);
          put_bits(p, 16, 0); /* patched later */
          avpriv_put_string(p, "CS=ITU601", 1);
          size = strlen("CS=ITU601")+3;
          AV_WB16(ptr, size);
      }
  }
  
  void ff_mjpeg_init_hvsample(AVCodecContext *avctx, int hsample[4], int vsample[4])
  {
      int chroma_h_shift, chroma_v_shift;
  
      av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &chroma_h_shift,
                                       &chroma_v_shift);
      if (avctx->codec->id == AV_CODEC_ID_LJPEG &&
          (   avctx->pix_fmt == AV_PIX_FMT_BGR0
           || avctx->pix_fmt == AV_PIX_FMT_BGRA
           || avctx->pix_fmt == AV_PIX_FMT_BGR24)) {
          vsample[0] = hsample[0] =
          vsample[1] = hsample[1] =
          vsample[2] = hsample[2] =
          vsample[3] = hsample[3] = 1;
      } else if (avctx->pix_fmt == AV_PIX_FMT_YUV444P || avctx->pix_fmt == AV_PIX_FMT_YUVJ444P) {
          vsample[0] = vsample[1] = vsample[2] = 2;
          hsample[0] = hsample[1] = hsample[2] = 1;
      } else {
          vsample[0] = 2;
          vsample[1] = 2 >> chroma_v_shift;
          vsample[2] = 2 >> chroma_v_shift;
          hsample[0] = 2;
          hsample[1] = 2 >> chroma_h_shift;
          hsample[2] = 2 >> chroma_h_shift;
      }
  }
  
  void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb,
                                      ScanTable *intra_scantable,
                                      uint16_t luma_intra_matrix[64],
                                      uint16_t chroma_intra_matrix[64])
  {
      const int lossless = avctx->codec_id != AV_CODEC_ID_MJPEG && avctx->codec_id != AV_CODEC_ID_AMV;
      int hsample[4], vsample[4];
      int i;
      int components = 3 + (avctx->pix_fmt == AV_PIX_FMT_BGRA);
      int chroma_matrix = !!memcmp(luma_intra_matrix,
                                   chroma_intra_matrix,
                                   sizeof(luma_intra_matrix[0])*64);
  
      ff_mjpeg_init_hvsample(avctx, hsample, vsample);
  
      put_marker(pb, SOI);
  
      // hack for AMV mjpeg format
      if(avctx->codec_id == AV_CODEC_ID_AMV) goto end;
  
      jpeg_put_comments(avctx, pb);
  
      jpeg_table_header(avctx, pb, intra_scantable, luma_intra_matrix, chroma_intra_matrix, hsample);
  
      switch (avctx->codec_id) {
      case AV_CODEC_ID_MJPEG:  put_marker(pb, SOF0 ); break;
      case AV_CODEC_ID_LJPEG:  put_marker(pb, SOF3 ); break;
      default: av_assert0(0);
      }
  
      put_bits(pb, 16, 17);
      if (lossless && (  avctx->pix_fmt == AV_PIX_FMT_BGR0
                      || avctx->pix_fmt == AV_PIX_FMT_BGRA
                      || avctx->pix_fmt == AV_PIX_FMT_BGR24))
          put_bits(pb, 8, 9); /* 9 bits/component RCT */
      else
          put_bits(pb, 8, 8); /* 8 bits/component */
      put_bits(pb, 16, avctx->height);
      put_bits(pb, 16, avctx->width);
      put_bits(pb, 8, components); /* 3 or 4 components */
  
      /* Y component */
      put_bits(pb, 8, 1); /* component number */
      put_bits(pb, 4, hsample[0]); /* H factor */
      put_bits(pb, 4, vsample[0]); /* V factor */
      put_bits(pb, 8, 0); /* select matrix */
  
      /* Cb component */
      put_bits(pb, 8, 2); /* component number */
      put_bits(pb, 4, hsample[1]); /* H factor */
      put_bits(pb, 4, vsample[1]); /* V factor */
      put_bits(pb, 8, lossless ? 0 : chroma_matrix); /* select matrix */
  
      /* Cr component */
      put_bits(pb, 8, 3); /* component number */
      put_bits(pb, 4, hsample[2]); /* H factor */
      put_bits(pb, 4, vsample[2]); /* V factor */
      put_bits(pb, 8, lossless ? 0 : chroma_matrix); /* select matrix */
  
      if (components == 4) {
          put_bits(pb, 8, 4); /* component number */
          put_bits(pb, 4, hsample[3]); /* H factor */
          put_bits(pb, 4, vsample[3]); /* V factor */
          put_bits(pb, 8, 0); /* select matrix */
      }
  
      /* scan header */
      put_marker(pb, SOS);
      put_bits(pb, 16, 6 + 2*components); /* length */
      put_bits(pb, 8, components); /* 3 components */
  
      /* Y component */
      put_bits(pb, 8, 1); /* index */
      put_bits(pb, 4, 0); /* DC huffman table index */
      put_bits(pb, 4, 0); /* AC huffman table index */
  
      /* Cb component */
      put_bits(pb, 8, 2); /* index */
      put_bits(pb, 4, 1); /* DC huffman table index */
      put_bits(pb, 4, lossless ? 0 : 1); /* AC huffman table index */
  
      /* Cr component */
      put_bits(pb, 8, 3); /* index */
      put_bits(pb, 4, 1); /* DC huffman table index */
      put_bits(pb, 4, lossless ? 0 : 1); /* AC huffman table index */
  
      if (components == 4) {
          /* Alpha component */
          put_bits(pb, 8, 4); /* index */
          put_bits(pb, 4, 0); /* DC huffman table index */
          put_bits(pb, 4, 0); /* AC huffman table index */
      }
  
      put_bits(pb, 8, lossless ? avctx->prediction_method + 1 : 0); /* Ss (not used) */
  
      switch (avctx->codec_id) {
      case AV_CODEC_ID_MJPEG:  put_bits(pb, 8, 63); break; /* Se (not used) */
      case AV_CODEC_ID_LJPEG:  put_bits(pb, 8,  0); break; /* not used */
      default: av_assert0(0);
      }
  
      put_bits(pb, 8, 0); /* Ah/Al (not used) */
  
  end:
      if (!lossless) {
          MpegEncContext *s = avctx->priv_data;
          av_assert0(avctx->codec->priv_data_size == sizeof(MpegEncContext));
  
          s->esc_pos = put_bits_count(pb) >> 3;
          for(i=1; i<s->slice_context_count; i++)
              s->thread_context[i]->esc_pos = 0;
      }
  }
  
  void ff_mjpeg_escape_FF(PutBitContext *pb, int start)
  {
      int size;
      int i, ff_count;
      uint8_t *buf = pb->buf + start;
      int align= (-(size_t)(buf))&3;
      int pad = (-put_bits_count(pb))&7;
  
      if (pad)
          put_bits(pb, pad, (1<<pad)-1);
  
      flush_put_bits(pb);
      size = put_bits_count(pb) - start * 8;
  
      av_assert1((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(pb);
      skip_put_bytes(pb, ff_count);
  
      for(i=size-1; ff_count; i--){
          int v= buf[i];
  
          if(v==0xFF){
              buf[i+ff_count]= 0;
              ff_count--;
          }
  
          buf[i+ff_count]= v;
      }
  }
  
  int ff_mjpeg_encode_stuffing(MpegEncContext *s)
  {
      int i;
      PutBitContext *pbc = &s->pb;
      int mb_y = s->mb_y - !s->mb_x;
  
      int ret = ff_mpv_reallocate_putbitbuffer(s, put_bits_count(&s->pb) / 8 + 100,
                                                  put_bits_count(&s->pb) / 4 + 1000);
      if (ret < 0) {
          av_log(s->avctx, AV_LOG_ERROR, "Buffer reallocation failed\n");
          goto fail;
      }
  
      ff_mjpeg_escape_FF(pbc, s->esc_pos);
  
      if((s->avctx->active_thread_type & FF_THREAD_SLICE) && mb_y < s->mb_height)
          put_marker(pbc, RST0 + (mb_y&7));
      s->esc_pos = put_bits_count(pbc) >> 3;
  fail:
  
      for(i=0; i<3; i++)
          s->last_dc[i] = 128 << s->intra_dc_precision;
  
      return ret;
  }
  
  void ff_mjpeg_encode_picture_trailer(PutBitContext *pb, int header_bits)
  {
      av_assert1((header_bits & 7) == 0);
  
      put_marker(pb, EOI);
  }
  
  void ff_mjpeg_encode_dc(PutBitContext *pb, int val,
                          uint8_t *huff_size, uint16_t *huff_code)
  {
      int mant, nbits;
  
      if (val == 0) {
          put_bits(pb, huff_size[0], huff_code[0]);
      } else {
          mant = val;
          if (val < 0) {
              val = -val;
              mant--;
          }
  
          nbits= av_log2_16bit(val) + 1;
  
          put_bits(pb, huff_size[nbits], huff_code[nbits]);
  
          put_sbits(pb, nbits, mant);
      }
  }
  