libavcodec/eatgq.c

   1 /*
   2  * Electronic Arts TGQ Video Decoder
   3  * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  20  */
  21
  22 /**
  23  * @file
  24  * Electronic Arts TGQ Video Decoder
  25  * @author Peter Ross <pross@xvid.org>
  26  *
  27  * Technical details here:
  28  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
  29  */
  30
  31 #include "avcodec.h"
  32 #define BITSTREAM_READER_LE
  33 #include "get_bits.h"
  34 #include "bytestream.h"
  35 #include "dsputil.h"
  36 #include "aandcttab.h"
  37 #include "eaidct.h"
  38 #include "internal.h"
  39
  40 typedef struct TgqContext {
  41     AVCodecContext *avctx;
  42     AVFrame frame;
  43     int width,height;
  44     ScanTable scantable;
  45     int qtable[64];
  46     DECLARE_ALIGNED(16, DCTELEM, block)[6][64];
  47     GetByteContext gb;
  48 } TgqContext;
  49
  50 static av_cold int tgq_decode_init(AVCodecContext *avctx){
  51     TgqContext *s = avctx->priv_data;
  52     uint8_t idct_permutation[64];
  53     s->avctx = avctx;
  54     ff_init_scantable_permutation(idct_permutation, FF_NO_IDCT_PERM);
  55     ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
  56     avctx->time_base = (AVRational){1, 15};
  57     avctx->pix_fmt = AV_PIX_FMT_YUV420P;
  58     return 0;
  59 }
  60
  61 static void tgq_decode_block(TgqContext *s, DCTELEM block[64], GetBitContext *gb){
  62     uint8_t *perm = s->scantable.permutated;
  63     int i,j,value;
  64     block[0] = get_sbits(gb,8) * s->qtable[0];
  65     for(i=1; i<64; ) {
  66         switch(show_bits(gb,3)) {
  67         case 4:
  68             block[perm[i++]] = 0;
  69         case 0:
  70             block[perm[i++]] = 0;
  71             skip_bits(gb,3);
  72             break;
  73         case 5:
  74         case 1:
  75             skip_bits(gb,2);
  76             value = get_bits(gb,6);
  77             for(j=0; j<value; j++)
  78                 block[perm[i++]] = 0;
  79             break;
  80         case 6:
  81             skip_bits(gb,3);
  82             block[perm[i]] = -s->qtable[perm[i]];
  83             i++;
  84             break;
  85         case 2:
  86             skip_bits(gb,3);
  87             block[perm[i]] = s->qtable[perm[i]];
  88             i++;
  89             break;
  90         case 7: // 111b
  91         case 3: // 011b
  92             skip_bits(gb,2);
  93             if (show_bits(gb,6)==0x3F) {
  94                 skip_bits(gb, 6);
  95                 block[perm[i]] = get_sbits(gb,8)*s->qtable[perm[i]];
  96             }else{
  97                 block[perm[i]] = get_sbits(gb,6)*s->qtable[perm[i]];
  98             }
  99             i++;
 100             break;
 101         }
 102     }
 103     block[0] += 128<<4;
 104 }
 105
 106 static void tgq_idct_put_mb(TgqContext *s, DCTELEM (*block)[64], int mb_x, int mb_y){
 107     int linesize= s->frame.linesize[0];
 108     uint8_t *dest_y  = s->frame.data[0] + (mb_y * 16* linesize            ) + mb_x * 16;
 109     uint8_t *dest_cb = s->frame.data[1] + (mb_y * 8 * s->frame.linesize[1]) + mb_x * 8;
 110     uint8_t *dest_cr = s->frame.data[2] + (mb_y * 8 * s->frame.linesize[2]) + mb_x * 8;
 111
 112     ff_ea_idct_put_c(dest_y                 , linesize, block[0]);
 113     ff_ea_idct_put_c(dest_y              + 8, linesize, block[1]);
 114     ff_ea_idct_put_c(dest_y + 8*linesize    , linesize, block[2]);
 115     ff_ea_idct_put_c(dest_y + 8*linesize + 8, linesize, block[3]);
 116     if(!(s->avctx->flags&CODEC_FLAG_GRAY)){
 117          ff_ea_idct_put_c(dest_cb, s->frame.linesize[1], block[4]);
 118          ff_ea_idct_put_c(dest_cr, s->frame.linesize[2], block[5]);
 119     }
 120 }
 121
 122 static inline void tgq_dconly(TgqContext *s, unsigned char *dst, int dst_stride, int dc){
 123     int level = av_clip_uint8((dc*s->qtable[0] + 2056)>>4);
 124     int j;
 125     for(j=0;j<8;j++)
 126         memset(dst+j*dst_stride, level, 8);
 127 }
 128
 129 static void tgq_idct_put_mb_dconly(TgqContext *s, int mb_x, int mb_y, const int8_t *dc)
 130 {
 131     int linesize= s->frame.linesize[0];
 132     uint8_t *dest_y  = s->frame.data[0] + (mb_y * 16* linesize            ) + mb_x * 16;
 133     uint8_t *dest_cb = s->frame.data[1] + (mb_y * 8 * s->frame.linesize[1]) + mb_x * 8;
 134     uint8_t *dest_cr = s->frame.data[2] + (mb_y * 8 * s->frame.linesize[2]) + mb_x * 8;
 135     tgq_dconly(s,dest_y                 , linesize, dc[0]);
 136     tgq_dconly(s,dest_y              + 8, linesize, dc[1]);
 137     tgq_dconly(s,dest_y + 8*linesize    , linesize, dc[2]);
 138     tgq_dconly(s,dest_y + 8*linesize + 8, linesize, dc[3]);
 139     if(!(s->avctx->flags&CODEC_FLAG_GRAY)) {
 140         tgq_dconly(s,dest_cb, s->frame.linesize[1], dc[4]);
 141         tgq_dconly(s,dest_cr, s->frame.linesize[2], dc[5]);
 142     }
 143 }
 144
 145 static void tgq_decode_mb(TgqContext *s, int mb_y, int mb_x){
 146     int mode;
 147     int i;
 148     int8_t dc[6];
 149
 150     mode = bytestream2_get_byte(&s->gb);
 151     if (mode>12) {
 152         GetBitContext gb;
 153         init_get_bits(&gb, s->gb.buffer, FFMIN(s->gb.buffer_end - s->gb.buffer, mode) * 8);
 154         for(i=0; i<6; i++)
 155             tgq_decode_block(s, s->block[i], &gb);
 156         tgq_idct_put_mb(s, s->block, mb_x, mb_y);
 157         bytestream2_skip(&s->gb, mode);
 158     }else{
 159         if (mode==3) {
 160             memset(dc, bytestream2_get_byte(&s->gb), 4);
 161             dc[4] = bytestream2_get_byte(&s->gb);
 162             dc[5] = bytestream2_get_byte(&s->gb);
 163         }else if (mode==6) {
 164             bytestream2_get_buffer(&s->gb, dc, 6);
 165         }else if (mode==12) {
 166             for (i = 0; i < 6; i++) {
 167                 dc[i] = bytestream2_get_byte(&s->gb);
 168                 bytestream2_skip(&s->gb, 1);
 169             }
 170         }else{
 171             av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
 172         }
 173         tgq_idct_put_mb_dconly(s, mb_x, mb_y, dc);
 174     }
 175 }
 176
 177 static void tgq_calculate_qtable(TgqContext *s, int quant){
 178     int i,j;
 179     const int a = (14*(100-quant))/100 + 1;
 180     const int b = (11*(100-quant))/100 + 4;
 181     for(j=0;j<8;j++)
 182     for(i=0;i<8;i++)
 183         s->qtable[j*8+i] = ((a*(j+i)/(7+7) + b)*ff_inv_aanscales[j*8+i])>>(14-4);
 184 }
 185
 186 static int tgq_decode_frame(AVCodecContext *avctx,
 187                             void *data, int *data_size,
 188                             AVPacket *avpkt){
 189     const uint8_t *buf = avpkt->data;
 190     int buf_size = avpkt->size;
 191     TgqContext *s = avctx->priv_data;
 192     int x,y;
 193     int big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
 194
 195     if (buf_size < 16) {
 196         av_log(avctx, AV_LOG_WARNING, "truncated header\n");
 197         return -1;
 198     }
 199     bytestream2_init(&s->gb, buf + 8, buf_size - 8);
 200     if (big_endian) {
 201         s->width  = bytestream2_get_be16u(&s->gb);
 202         s->height = bytestream2_get_be16u(&s->gb);
 203     } else {
 204         s->width  = bytestream2_get_le16u(&s->gb);
 205         s->height = bytestream2_get_le16u(&s->gb);
 206     }
 207
 208     if (s->avctx->width!=s->width || s->avctx->height!=s->height) {
 209         avcodec_set_dimensions(s->avctx, s->width, s->height);
 210         if (s->frame.data[0])
 211             avctx->release_buffer(avctx, &s->frame);
 212     }
 213     tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
 214     bytestream2_skip(&s->gb, 3);
 215
 216     if (!s->frame.data[0]) {
 217         s->frame.key_frame = 1;
 218         s->frame.pict_type = AV_PICTURE_TYPE_I;
 219         s->frame.buffer_hints = FF_BUFFER_HINTS_VALID;
 220         if (ff_get_buffer(avctx, &s->frame)) {
 221             av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 222             return -1;
 223         }
 224     }
 225
 226     for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
 227         for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
 228             tgq_decode_mb(s, y, x);
 229
 230     *data_size = sizeof(AVFrame);
 231     *(AVFrame*)data = s->frame;
 232
 233     return avpkt->size;
 234 }
 235
 236 static av_cold int tgq_decode_end(AVCodecContext *avctx){
 237     TgqContext *s = avctx->priv_data;
 238     if (s->frame.data[0])
 239         s->avctx->release_buffer(avctx, &s->frame);
 240     return 0;
 241 }
 242
 243 AVCodec ff_eatgq_decoder = {
 244     .name           = "eatgq",
 245     .type           = AVMEDIA_TYPE_VIDEO,
 246     .id             = AV_CODEC_ID_TGQ,
 247     .priv_data_size = sizeof(TgqContext),
 248     .init           = tgq_decode_init,
 249     .close          = tgq_decode_end,
 250     .decode         = tgq_decode_frame,
 251     .capabilities   = CODEC_CAP_DR1,
 252     .long_name      = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
 253 };