ffmpeg/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
  24  * Intel Indeo 2 decoder.
  25  */
  26
  27 #define BITSTREAM_READER_LE
  28 #include "libavutil/attributes.h"
  29 #include "avcodec.h"
  30 #include "get_bits.h"
  31 #include "indeo2data.h"
  32 #include "internal.h"
  33 #include "mathops.h"
  34
  35 typedef struct Ir2Context{
  36     AVCodecContext *avctx;
  37     AVFrame *picture;
  38     GetBitContext gb;
  39     int decode_delta;
  40 } Ir2Context;
  41
  42 #define CODE_VLC_BITS 14
  43 static VLC ir2_vlc;
  44
  45 /* Indeo 2 codes are in range 0x01..0x7F and 0x81..0x90 */
  46 static inline int ir2_get_code(GetBitContext *gb)
  47 {
  48     return get_vlc2(gb, ir2_vlc.table, CODE_VLC_BITS, 1) + 1;
  49 }
  50
  51 static int ir2_decode_plane(Ir2Context *ctx, int width, int height, uint8_t *dst,
  52                             int pitch, const uint8_t *table)
  53 {
  54     int i;
  55     int j;
  56     int out = 0;
  57
  58     if (width & 1)
  59         return AVERROR_INVALIDDATA;
  60
  61     /* first line contain absolute values, other lines contain deltas */
  62     while (out < width) {
  63         int c = ir2_get_code(&ctx->gb);
  64         if (c >= 0x80) { /* we have a run */
  65             c -= 0x7F;
  66             if (out + c*2 > width)
  67                 return AVERROR_INVALIDDATA;
  68             for (i = 0; i < c * 2; i++)
  69                 dst[out++] = 0x80;
  70         } else { /* copy two values from table */
  71             dst[out++] = table[c * 2];
  72             dst[out++] = table[(c * 2) + 1];
  73         }
  74     }
  75     dst += pitch;
  76
  77     for (j = 1; j < height; j++) {
  78         out = 0;
  79         while (out < width) {
  80             int c = ir2_get_code(&ctx->gb);
  81             if (c >= 0x80) { /* we have a skip */
  82                 c -= 0x7F;
  83                 if (out + c*2 > width)
  84                     return AVERROR_INVALIDDATA;
  85                 for (i = 0; i < c * 2; i++) {
  86                     dst[out] = dst[out - pitch];
  87                     out++;
  88                 }
  89             } else { /* add two deltas from table */
  90                 int t    = dst[out - pitch] + (table[c * 2] - 128);
  91                 t        = av_clip_uint8(t);
  92                 dst[out] = t;
  93                 out++;
  94                 t        = dst[out - pitch] + (table[(c * 2) + 1] - 128);
  95                 t        = av_clip_uint8(t);
  96                 dst[out] = t;
  97                 out++;
  98             }
  99         }
 100         dst += pitch;
 101     }
 102     return 0;
 103 }
 104
 105 static int ir2_decode_plane_inter(Ir2Context *ctx, int width, int height, uint8_t *dst,
 106                                   int pitch, const uint8_t *table)
 107 {
 108     int j;
 109     int out = 0;
 110     int c;
 111     int t;
 112
 113     if (width & 1)
 114         return AVERROR_INVALIDDATA;
 115
 116     for (j = 0; j < height; j++) {
 117         out = 0;
 118         while (out < width) {
 119             c = ir2_get_code(&ctx->gb);
 120             if (c >= 0x80) { /* we have a skip */
 121                 c   -= 0x7F;
 122                 out += c * 2;
 123             } else { /* add two deltas from table */
 124                 t        = dst[out] + (((table[c * 2] - 128)*3) >> 2);
 125                 t        = av_clip_uint8(t);
 126                 dst[out] = t;
 127                 out++;
 128                 t        = dst[out] + (((table[(c * 2) + 1] - 128)*3) >> 2);
 129                 t        = av_clip_uint8(t);
 130                 dst[out] = t;
 131                 out++;
 132             }
 133         }
 134         dst += pitch;
 135     }
 136     return 0;
 137 }
 138
 139 static int ir2_decode_frame(AVCodecContext *avctx,
 140                         void *data, int *got_frame,
 141                         AVPacket *avpkt)
 142 {
 143     Ir2Context * const s = avctx->priv_data;
 144     const uint8_t *buf   = avpkt->data;
 145     int buf_size         = avpkt->size;
 146     AVFrame *picture     = data;
 147     AVFrame * const p    = s->picture;
 148     int start, ret;
 149
 150     if ((ret = ff_reget_buffer(avctx, p)) < 0)
 151         return ret;
 152
 153     start = 48; /* hardcoded for now */
 154
 155     if (start >= buf_size) {
 156         av_log(s->avctx, AV_LOG_ERROR, "input buffer size too small (%d)\n", buf_size);
 157         return AVERROR_INVALIDDATA;
 158     }
 159
 160     s->decode_delta = buf[18];
 161
 162     /* decide whether frame uses deltas or not */
 163 #ifndef BITSTREAM_READER_LE
 164     for (i = 0; i < buf_size; i++)
 165         buf[i] = ff_reverse[buf[i]];
 166 #endif
 167
 168     init_get_bits(&s->gb, buf + start, (buf_size - start) * 8);
 169
 170     if (s->decode_delta) { /* intraframe */
 171         if ((ret = ir2_decode_plane(s, avctx->width, avctx->height,
 172                                     p->data[0], p->linesize[0],
 173                                     ir2_luma_table)) < 0)
 174             return ret;
 175
 176         /* swapped U and V */
 177         if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
 178                                     p->data[2], p->linesize[2],
 179                                     ir2_luma_table)) < 0)
 180             return ret;
 181         if ((ret = ir2_decode_plane(s, avctx->width >> 2, avctx->height >> 2,
 182                                     p->data[1], p->linesize[1],
 183                                     ir2_luma_table)) < 0)
 184             return ret;
 185     } else { /* interframe */
 186         if ((ret = ir2_decode_plane_inter(s, avctx->width, avctx->height,
 187                                           p->data[0], p->linesize[0],
 188                                           ir2_luma_table)) < 0)
 189             return ret;
 190         /* swapped U and V */
 191         if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
 192                                           p->data[2], p->linesize[2],
 193                                           ir2_luma_table)) < 0)
 194             return ret;
 195         if ((ret = ir2_decode_plane_inter(s, avctx->width >> 2, avctx->height >> 2,
 196                                           p->data[1], p->linesize[1],
 197                                           ir2_luma_table)) < 0)
 198             return ret;
 199     }
 200
 201     if ((ret = av_frame_ref(picture, p)) < 0)
 202         return ret;
 203
 204     *got_frame = 1;
 205
 206     return buf_size;
 207 }
 208
 209 static av_cold int ir2_decode_init(AVCodecContext *avctx)
 210 {
 211     Ir2Context * const ic = avctx->priv_data;
 212     static VLC_TYPE vlc_tables[1 << CODE_VLC_BITS][2];
 213
 214     ic->avctx = avctx;
 215
 216     avctx->pix_fmt= AV_PIX_FMT_YUV410P;
 217
 218     ic->picture = av_frame_alloc();
 219     if (!ic->picture)
 220         return AVERROR(ENOMEM);
 221
 222     ir2_vlc.table = vlc_tables;
 223     ir2_vlc.table_allocated = 1 << CODE_VLC_BITS;
 224 #ifdef BITSTREAM_READER_LE
 225         init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
 226                  &ir2_codes[0][1], 4, 2,
 227                  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC | INIT_VLC_LE);
 228 #else
 229         init_vlc(&ir2_vlc, CODE_VLC_BITS, IR2_CODES,
 230                  &ir2_codes[0][1], 4, 2,
 231                  &ir2_codes[0][0], 4, 2, INIT_VLC_USE_NEW_STATIC);
 232 #endif
 233
 234     return 0;
 235 }
 236
 237 static av_cold int ir2_decode_end(AVCodecContext *avctx)
 238 {
 239     Ir2Context * const ic = avctx->priv_data;
 240
 241     av_frame_free(&ic->picture);
 242
 243     return 0;
 244 }
 245
 246 AVCodec ff_indeo2_decoder = {
 247     .name           = "indeo2",
 248     .long_name      = NULL_IF_CONFIG_SMALL("Intel Indeo 2"),
 249     .type           = AVMEDIA_TYPE_VIDEO,
 250     .id             = AV_CODEC_ID_INDEO2,
 251     .priv_data_size = sizeof(Ir2Context),
 252     .init           = ir2_decode_init,
 253     .close          = ir2_decode_end,
 254     .decode         = ir2_decode_frame,
 255     .capabilities   = CODEC_CAP_DR1,
 256 };