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, int16_t, block)[6][64];
  47     GetByteContext gb;
  48 } TgqContext;
  49
  50 static av_cold int tgq_decode_init(AVCodecContext *avctx)
  51 {
  52     TgqContext *s = avctx->priv_data;
  53     uint8_t idct_permutation[64];
  54     s->avctx = avctx;
  55     ff_init_scantable_permutation(idct_permutation, FF_NO_IDCT_PERM);
  56     ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
  57     avctx->time_base = (AVRational){1, 15};
  58     avctx->pix_fmt   = AV_PIX_FMT_YUV420P;
  59     return 0;
  60 }
  61
  62 static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
  63 {
  64     uint8_t *perm = s->scantable.permutated;
  65     int i, j, value;
  66     block[0] = get_sbits(gb, 8) * s->qtable[0];
  67     for (i = 1; i < 64;) {
  68         switch (show_bits(gb, 3)) {
  69         case 4:
  70             block[perm[i++]] = 0;
  71         case 0:
  72             block[perm[i++]] = 0;
  73             skip_bits(gb, 3);
  74             break;
  75         case 5:
  76         case 1:
  77             skip_bits(gb, 2);
  78             value = get_bits(gb, 6);
  79             for (j = 0; j < value; j++)
  80                 block[perm[i++]] = 0;
  81             break;
  82         case 6:
  83             skip_bits(gb, 3);
  84             block[perm[i]] = -s->qtable[perm[i]];
  85             i++;
  86             break;
  87         case 2:
  88             skip_bits(gb, 3);
  89             block[perm[i]] = s->qtable[perm[i]];
  90             i++;
  91             break;
  92         case 7: // 111b
  93         case 3: // 011b
  94             skip_bits(gb, 2);
  95             if (show_bits(gb, 6) == 0x3F) {
  96                 skip_bits(gb, 6);
  97                 block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
  98             } else {
  99                 block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
 100             }
 101             i++;
 102             break;
 103         }
 104     }
 105     block[0] += 128 << 4;
 106 }
 107
 108 static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64],
 109                             int mb_x, int mb_y)
 110 {
 111     int linesize = s->frame.linesize[0];
 112     uint8_t *dest_y  = s->frame.data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
 113     uint8_t *dest_cb = s->frame.data[1] + (mb_y * 8  * s->frame.linesize[1]) + mb_x * 8;
 114     uint8_t *dest_cr = s->frame.data[2] + (mb_y * 8  * s->frame.linesize[2]) + mb_x * 8;
 115
 116     ff_ea_idct_put_c(dest_y                   , linesize, block[0]);
 117     ff_ea_idct_put_c(dest_y                + 8, linesize, block[1]);
 118     ff_ea_idct_put_c(dest_y + 8 * linesize    , linesize, block[2]);
 119     ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
 120     if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
 121          ff_ea_idct_put_c(dest_cb, s->frame.linesize[1], block[4]);
 122          ff_ea_idct_put_c(dest_cr, s->frame.linesize[2], block[5]);
 123     }
 124 }
 125
 126 static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
 127                               int dst_stride, int dc)
 128 {
 129     int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
 130     int j;
 131     for (j = 0; j < 8; j++)
 132         memset(dst + j * dst_stride, level, 8);
 133 }
 134
 135 static void tgq_idct_put_mb_dconly(TgqContext *s, int mb_x, int mb_y, const int8_t *dc)
 136 {
 137     int linesize = s->frame.linesize[0];
 138     uint8_t *dest_y  = s->frame.data[0] + (mb_y * 16 * linesize)             + mb_x * 16;
 139     uint8_t *dest_cb = s->frame.data[1] + (mb_y * 8  * s->frame.linesize[1]) + mb_x * 8;
 140     uint8_t *dest_cr = s->frame.data[2] + (mb_y * 8  * s->frame.linesize[2]) + mb_x * 8;
 141     tgq_dconly(s, dest_y,                    linesize, dc[0]);
 142     tgq_dconly(s, dest_y                + 8, linesize, dc[1]);
 143     tgq_dconly(s, dest_y + 8 * linesize,     linesize, dc[2]);
 144     tgq_dconly(s, dest_y + 8 * linesize + 8, linesize, dc[3]);
 145     if (!(s->avctx->flags & CODEC_FLAG_GRAY)) {
 146         tgq_dconly(s, dest_cb, s->frame.linesize[1], dc[4]);
 147         tgq_dconly(s, dest_cr, s->frame.linesize[2], dc[5]);
 148     }
 149 }
 150
 151 static void tgq_decode_mb(TgqContext *s, int mb_y, int mb_x)
 152 {
 153     int mode;
 154     int i;
 155     int8_t dc[6];
 156
 157     mode = bytestream2_get_byte(&s->gb);
 158     if (mode > 12) {
 159         GetBitContext gb;
 160         init_get_bits(&gb, s->gb.buffer, FFMIN(s->gb.buffer_end - s->gb.buffer, mode) * 8);
 161         for (i = 0; i < 6; i++)
 162             tgq_decode_block(s, s->block[i], &gb);
 163         tgq_idct_put_mb(s, s->block, mb_x, mb_y);
 164         bytestream2_skip(&s->gb, mode);
 165     } else {
 166         if (mode == 3) {
 167             memset(dc, bytestream2_get_byte(&s->gb), 4);
 168             dc[4] = bytestream2_get_byte(&s->gb);
 169             dc[5] = bytestream2_get_byte(&s->gb);
 170         } else if (mode == 6) {
 171             bytestream2_get_buffer(&s->gb, dc, 6);
 172         } else if (mode == 12) {
 173             for (i = 0; i < 6; i++) {
 174                 dc[i] = bytestream2_get_byte(&s->gb);
 175                 bytestream2_skip(&s->gb, 1);
 176             }
 177         } else {
 178             av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
 179         }
 180         tgq_idct_put_mb_dconly(s, mb_x, mb_y, dc);
 181     }
 182 }
 183
 184 static void tgq_calculate_qtable(TgqContext *s, int quant)
 185 {
 186     int i, j;
 187     const int a = (14 * (100 - quant)) / 100 + 1;
 188     const int b = (11 * (100 - quant)) / 100 + 4;
 189     for (j = 0; j < 8; j++)
 190         for (i = 0; i < 8; i++)
 191             s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
 192                                     ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
 193 }
 194
 195 static int tgq_decode_frame(AVCodecContext *avctx,
 196                             void *data, int *got_frame,
 197                             AVPacket *avpkt)
 198 {
 199     const uint8_t *buf = avpkt->data;
 200     int buf_size       = avpkt->size;
 201     TgqContext *s      = avctx->priv_data;
 202     int x, y, ret;
 203     int big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
 204
 205     if (buf_size < 16) {
 206         av_log(avctx, AV_LOG_WARNING, "truncated header\n");
 207         return AVERROR_INVALIDDATA;
 208     }
 209     bytestream2_init(&s->gb, buf + 8, buf_size - 8);
 210     if (big_endian) {
 211         s->width  = bytestream2_get_be16u(&s->gb);
 212         s->height = bytestream2_get_be16u(&s->gb);
 213     } else {
 214         s->width  = bytestream2_get_le16u(&s->gb);
 215         s->height = bytestream2_get_le16u(&s->gb);
 216     }
 217
 218     if (s->avctx->width!=s->width || s->avctx->height!=s->height) {
 219         avcodec_set_dimensions(s->avctx, s->width, s->height);
 220         if (s->frame.data[0])
 221             avctx->release_buffer(avctx, &s->frame);
 222     }
 223     tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
 224     bytestream2_skip(&s->gb, 3);
 225
 226     if (!s->frame.data[0]) {
 227         s->frame.key_frame = 1;
 228         s->frame.pict_type = AV_PICTURE_TYPE_I;
 229         s->frame.buffer_hints = FF_BUFFER_HINTS_VALID;
 230         if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
 231             av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
 232             return ret;
 233         }
 234     }
 235
 236     for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
 237         for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
 238             tgq_decode_mb(s, y, x);
 239
 240     *got_frame = 1;
 241     *(AVFrame*)data = s->frame;
 242
 243     return avpkt->size;
 244 }
 245
 246 static av_cold int tgq_decode_end(AVCodecContext *avctx)
 247 {
 248     TgqContext *s = avctx->priv_data;
 249     if (s->frame.data[0])
 250         s->avctx->release_buffer(avctx, &s->frame);
 251     return 0;
 252 }
 253
 254 AVCodec ff_eatgq_decoder = {
 255     .name           = "eatgq",
 256     .type           = AVMEDIA_TYPE_VIDEO,
 257     .id             = AV_CODEC_ID_TGQ,
 258     .priv_data_size = sizeof(TgqContext),
 259     .init           = tgq_decode_init,
 260     .close          = tgq_decode_end,
 261     .decode         = tgq_decode_frame,
 262     .capabilities   = CODEC_CAP_DR1,
 263     .long_name      = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
 264 };