extern/ffmpeg/libavcodec/indeo2.c

   1 /*
   2  * Indel Indeo 2 codec
   3  * Copyright (c) 2005 Konstantin Shishkov
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18  *
  19  */
  20
  21 /**
  22  * @file indeo2.c
  23  * Intel Indeo 2 decoder.
  24  */
  25 #define ALT_BITSTREAM_READER_LE
  26 #include "avcodec.h"
  27 #include "bitstream.h"
  28 #include "indeo2data.h"
  29
  30 typedef struct Ir2Context{
  31     AVCodecContext *avctx;
  32     AVFrame picture;
  33     GetBitContext gb;
  34     int decode_delta;
  35 } Ir2Context;
  36
  37 #define CODE_VLC_BITS 14
  38 static VLC ir2_vlc;
  39
  40 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
  41 static inline int ir2_get_code(GetBitContext *gb)
  42 {
  43     return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
  44 }
  45
  46 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
  47                              const uint8_t *table)
  48 {
  49     int i;
  50     int j;
  51     int out = 0;
  52     int c;
  53     int t;
  54
  55     if(width&1)
  56         return -1;
  57
  58     /* first line contain absolute values, other lines contain deltas */
  59     while (out < width){
  60         c = ir2_get_code(&ctx->gb);
  61         if(c >= 0x80) { /* we have a run */
  62             c -= 0x7F;
  63             if(out + c*2 > width)
  64                 return -1;
  65             for (i = 0; i < c * 2; i++)
  66                 dst[out++] = 0x80;
  67         } else { /* copy two values from table */
  68             dst[out++] = table[c * 2];
  69             dst[out++] = table[(c * 2) + 1];
  70         }
  71     }
  72     dst += stride;
  73
  74     for (j = 1; j < height; j++){
  75         out = 0;
  76         while (out < width){
  77             c = ir2_get_code(&ctx->gb);
  78             if(c >= 0x80) { /* we have a skip */
  79                 c -= 0x7F;
  80                 if(out + c*2 > width)
  81                     return -1;
  82                 for (i = 0; i < c * 2; i++) {
  83                     dst[out] = dst[out - stride];
  84                     out++;
  85                 }
  86             } else { /* add two deltas from table */
  87                 t = dst[out - stride] + (table[c * 2] - 128);
  88                 t= clip_uint8(t);
  89                 dst[out] = t;
  90                 out++;
  91                 t = dst[out - stride] + (table[(c * 2) + 1] - 128);
  92                 t= clip_uint8(t);
  93                 dst[out] = t;
  94                 out++;
  95             }
  96         }
  97         dst += stride;
  98     }
  99     return 0;
 100 }
 101
 102 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst, int stride,
 103                              const uint8_t *table)
 104 {
 105     int j;
 106     int out = 0;
 107     int c;
 108     int t;
 109
 110     if(width&1)
 111         return -1;
 112
 113     for (j = 0; j < height; j++){
 114         out = 0;
 115         while (out < width){
 116             c = ir2_get_code(&ctx->gb);
 117             if(c >= 0x80) { /* we have a skip */
 118                 c -= 0x7F;
 119                 out += c * 2;
 120             } else { /* add two deltas from table */
 121                 t = dst[out] + (((table[c * 2] - 128)*3) >> 2);
 122                 t= clip_uint8(t);
 123                 dst[out] = t;
 124                 out++;
 125                 t = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
 126                 t= clip_uint8(t);
 127                 dst[out] = t;
 128                 out++;
 129             }
 130         }
 131         dst += stride;
 132     }
 133     return 0;
 134 }
 135
 136 static int ir2_decode_frame(AVCodecContext *avctx,
 137                         void *data, int *data_size,
 138                         uint8_t *buf, int buf_size)
 139 {
 140     Ir2Context * const s = avctx->priv_data;
 141     AVFrame *picture = data;
 142     AVFrame * const p= (AVFrame*)&s->picture;
 143     int start;
 144
 145     if(p->data[0])
 146         avctx->release_buffer(avctx, p);
 147
 148     p->reference = 1;
 149     p->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
 150     if (avctx->reget_buffer(avctx, p)) {
 151         av_log(s->avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
 152         return -1;
 153     }
 154
 155     s->decode_delta = buf[18];
 156
 157     /* decide whether frame uses deltas or not */
 158 #ifndef ALT_BITSTREAM_READER_LE
 159     for (i = 0; i < buf_size; i++)
 160         buf[i] = ff_reverse[buf[i]];
 161 #endif
 162     start = 48; /* hardcoded for now */
 163
 164     init_get_bits(&s->gb, buf + start, buf_size - start);
 165
 166     if (s->decode_delta) { /* intraframe */
 167         ir2_decode_plane(s, avctx->width, avctx->height,
 168                          s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
 169         /* swapped U and V */
 170         ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
 171                          s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
 172         ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
 173                          s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
 174     } else { /* interframe */
 175         ir2_decode_plane_inter(s, avctx->width, avctx->height,
 176                          s->picture.data[0], s->picture.linesize[0], ir2_luma_table);
 177         /* swapped U and V */
 178         ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
 179                          s->picture.data[2], s->picture.linesize[2], ir2_luma_table);
 180         ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
 181                          s->picture.data[1], s->picture.linesize[1], ir2_luma_table);
 182     }
 183
 184     *picture= *(AVFrame*)&s->picture;
 185     *data_size = sizeof(AVPicture);
 186
 187     return buf_size;
 188 }
 189
 190 static int ir2_decode_init(AVCodecContext *avctx){
 191     Ir2Context * const ic = avctx->priv_data;
 192
 193     ic->avctx = avctx;
 194
 195     avctx->pix_fmt= PIX_FMT_YUV410P;
 196
 197     if (!ir2_vlc.table)
 198         init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
 199                  &ir2_codes[0][1], 4, 2,
 200 #ifdef ALT_BITSTREAM_READER_LE
 201                  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_STATIC | INIT_VLC_LE);
 202 #else
 203                  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_STATIC);
 204 #endif
 205
 206     return 0;
 207 }
 208
 209 AVCodec indeo2_decoder = {
 210     "indeo2",
 211     CODEC_TYPE_VIDEO,
 212     CODEC_ID_INDEO2,
 213     sizeof(Ir2Context),
 214     ir2_decode_init,
 215     NULL,
 216     NULL,
 217     ir2_decode_frame,
 218     CODEC_CAP_DR1,
 219 };