libavcodec/indeo2.c

   1 /*
   2  * Intel Indeo 2 codec
   3  * Copyright (c) 2005 Konstantin Shishkov
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file libavcodec/indeo2.c
  24  * Intel Indeo 2 decoder.
  25  */
  26 #define ALT_BITSTREAM_READER_LE
  27 #include "avcodec.h"
  28 #include "get_bits.h"
  29 #include "indeo2data.h"
  30
  31 typedef struct Ir2Context{
  32     AVCodecContext *avctx;
  33     AVFrame picture;
  34     GetBitContext gb;
  35     int decode_delta;
  36 } Ir2Context;
  37
  38 #define CODE_VLC_BITS 14
  39 static VLC ir2_vlc;
  40
  41 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
  42 static inline int ir2_get_code(GetBitContext *gb)
  43 {
  44     return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
  45 }
  46
  47 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
  48                              const uint8_t *table)
  49 {
  50     int i;
  51     int j;
  52     int out = 0;
  53     int c;
  54     int t;
  55
  56     if(width&1)
  57         return -1;
  58
  59     /* first line contain absolute values, other lines contain deltas */
  60     while (out < width){
  61         c = ir2_get_code(&ctx->gb);
  62         if(c >= 0x80) { /* we have a run */
  63             c -= 0x7F;
  64             if(out + c*2 > width)
  65                 return -1;
  66             for (i = 0; i < c * 2; i++)
  67                 dst[out++] = 0x80;
  68         } else { /* copy two values from table */
  69             dst[out++] = table[c * 2];
  70             dst[out++] = table[(c * 2) + 1];
  71         }
  72     }
  73     dst += stride;
  74
  75     for (j = 1; j < height; j++){
  76         out = 0;
  77         while (out < width){
  78             c = ir2_get_code(&ctx->gb);
  79             if(c >= 0x80) { /* we have a skip */
  80                 c -= 0x7F;
  81                 if(out + c*2 > width)
  82                     return -1;
  83                 for (i = 0; i < c * 2; i++) {
  84                     dst[out] = dst[out - stride];
  85                     out++;
  86                 }
  87             } else { /* add two deltas from table */
  88                 t = dst[out - stride] + (table[c * 2] - 128);
  89                 t= av_clip_uint8(t);
  90                 dst[out] = t;
  91                 out++;
  92                 t = dst[out - stride] + (table[(c * 2) + 1] - 128);
  93                 t= av_clip_uint8(t);
  94                 dst[out] = t;
  95                 out++;
  96             }
  97         }
  98         dst += stride;
  99     }
 100     return 0;
 101 }
 102
 103 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
 104                              const uint8_t *table)
 105 {
 106     int j;
 107     int out = 0;
 108     int c;
 109     int t;
 110
 111     if(width&1)
 112         return -1;
 113
 114     for (j = 0; j < height; j++){
 115         out = 0;
 116         while (out < width){
 117             c = ir2_get_code(&ctx->gb);
 118             if(c >= 0x80) { /* we have a skip */
 119                 c -= 0x7F;
 120                 out += c * 2;
 121             } else { /* add two deltas from table */
 122                 t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
 123                 t= av_clip_uint8(t);
 124                 dst[out] = t;
 125                 out++;
 126                 t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
 127                 t= av_clip_uint8(t);
 128                 dst[out] = t;
 129                 out++;
 130             }
 131         }
 132         dst += stride;
 133     }
 134     return 0;
 135 }
 136
 137 static int ir2_decode_frame(AVCodecContext *avctx,
 138                         void *data, int *data_size,
 139                         AVPacket *avpkt)
 140 {
 141     const uint8_t *buf = avpkt->data;
 142     int buf_size = avpkt->size;
 143     Ir2Context * const s = avctx->priv_data;
 144     AVFrame *picture = data;
 145     AVFrame * const p= (AVFrame*)&s->picture;
 146     int start;
 147
 148     if(p->data[0])
 149         avctx->release_buffer(avctx, p);
 150
 151     p->reference = 1;
 152     p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
 153     if (avctx->reget_buffer(avctx, p)) {
 154         av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 155         return -1;
 156     }
 157
 158     s->decode_delta = buf[18];
 159
 160     /* decide whether frame uses deltas or not */
 161 #ifndef ALT_BITSTREAM_READER_LE
 162     for (i = 0; i < buf_size; i++)
 163         buf[i] = ff_reverse[buf[i]];
 164 #endif
 165     start = 48; /* hardcoded for now */
 166
 167     init_get_bits(&s->gb, buf + start, buf_size - start);
 168
 169     if (s->decode_delta) { /* intraframe */
 170         ir2_decode_plane(s, avctx->width, avctx->height,
 171                          s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
 172         /* swapped U and V */
 173         ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
 174                          s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
 175         ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
 176                          s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
 177     } else { /* interframe */
 178         ir2_decode_plane_inter(s, avctx->width, avctx->height,
 179                          s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
 180         /* swapped U and V */
 181         ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
 182                          s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
 183         ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
 184                          s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
 185     }
 186
 187     *picture= *(AVFrame*)&s->picture;
 188     *data_size = sizeof(AVPicture);
 189
 190     return buf_size;
 191 }
 192
 193 static av_cold int ir2_decode_init(AVCodecContext *avctx){
 194     Ir2Context * const ic = avctx->priv_data;
 195     static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
 196
 197     ic->avctx = avctx;
 198
 199     avctx->pix_fmt= PIX_FMT_YUV410P;
 200
 201     ir2_vlc.table = vlc_tables;
 202     ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
 203 #ifdef ALT_BITSTREAM_READER_LE
 204         init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
 205                  &ir2_codes[0][1], 4, 2,
 206                  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE);
 207 #else
 208         init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
 209                  &ir2_codes[0][1], 4, 2,
 210                  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
 211 #endif
 212
 213     return 0;
 214 }
 215
 216 AVCodec indeo2_decoder = {
 217     "indeo2",
 218     CODEC_TYPE_VIDEO,
 219     CODEC_ID_INDEO2,
 220     sizeof(Ir2Context),
 221     ir2_decode_init,
 222     NULL,
 223     NULL,
 224     ir2_decode_frame,
 225     CODEC_CAP_DR1,
 226     .long_name = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
 227 };