2 * Electronic Arts TGQ Video Decoder
3 * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
5 * This file is part of FFmpeg.
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.
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.
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 St, Fifth Floor, Boston, MA 02110-1301 USA
23 * @file libavcodec/eatgq.c
24 * Electronic Arts TGQ Video Decoder
25 * @author Peter Ross <pross@xvid.org>
27 * Technical details here:
28 * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_TGQ
32 #define ALT_BITSTREAM_READER_LE
33 #include "bitstream.h"
34 #include "bytestream.h"
36 #include "aandcttab.h"
38 typedef struct TgqContext {
39 AVCodecContext *avctx;
47 static av_cold int tgq_decode_init(AVCodecContext *avctx){
48 TgqContext *s = avctx->priv_data;
50 if(avctx->idct_algo==FF_IDCT_AUTO)
51 avctx->idct_algo=FF_IDCT_EA;
52 dsputil_init(&s->dsp, avctx);
53 ff_init_scantable(s->dsp.idct_permutation, &s->scantable, ff_zigzag_direct);
54 avctx->time_base = (AVRational){1, 15};
55 avctx->pix_fmt = PIX_FMT_YUV420P;
59 static void tgq_decode_block(TgqContext *s, DCTELEM block[64], GetBitContext *gb){
60 uint8_t *perm = s->scantable.permutated;
62 block[0] = get_sbits(gb,8) * s->qtable[0];
64 switch(show_bits(gb,3)) {
74 value = get_bits(gb,6);
75 for(j=0; j<value; j++)
80 block[perm[i]] = -s->qtable[perm[i]];
85 block[perm[i]] = s->qtable[perm[i]];
91 if (show_bits(gb,6)==0x3F) {
93 block[perm[i]] = get_sbits(gb,8)*s->qtable[perm[i]];
95 block[perm[i]] = get_sbits(gb,6)*s->qtable[perm[i]];
104 static void tgq_idct_put_mb(TgqContext *s, DCTELEM (*block)[64], int mb_x, int mb_y){
105 int linesize= s->frame.linesize[0];
106 uint8_t *dest_y = s->frame.data[0] + (mb_y * 16* linesize ) + mb_x * 16;
107 uint8_t *dest_cb = s->frame.data[1] + (mb_y * 8 * s->frame.linesize[1]) + mb_x * 8;
108 uint8_t *dest_cr = s->frame.data[2] + (mb_y * 8 * s->frame.linesize[2]) + mb_x * 8;
110 s->dsp.idct_put(dest_y , linesize, block[0]);
111 s->dsp.idct_put(dest_y + 8, linesize, block[1]);
112 s->dsp.idct_put(dest_y + 8*linesize , linesize, block[2]);
113 s->dsp.idct_put(dest_y + 8*linesize + 8, linesize, block[3]);
114 if(!(s->avctx->flags&CODEC_FLAG_GRAY)){
115 s->dsp.idct_put(dest_cb, s->frame.linesize[1], block[4]);
116 s->dsp.idct_put(dest_cr, s->frame.linesize[2], block[5]);
120 static inline void tgq_dconly(TgqContext *s, unsigned char *dst, int dst_stride, int dc){
121 int level = av_clip_uint8((dc*s->qtable[0] + 2056)>>4);
124 memset(dst+j*dst_stride, level, 8);
127 static void tgq_idct_put_mb_dconly(TgqContext *s, int mb_x, int mb_y, const int8_t *dc)
129 int linesize= s->frame.linesize[0];
130 uint8_t *dest_y = s->frame.data[0] + (mb_y * 16* linesize ) + mb_x * 16;
131 uint8_t *dest_cb = s->frame.data[1] + (mb_y * 8 * s->frame.linesize[1]) + mb_x * 8;
132 uint8_t *dest_cr = s->frame.data[2] + (mb_y * 8 * s->frame.linesize[2]) + mb_x * 8;
133 tgq_dconly(s,dest_y , linesize, dc[0]);
134 tgq_dconly(s,dest_y + 8, linesize, dc[1]);
135 tgq_dconly(s,dest_y + 8*linesize , linesize, dc[2]);
136 tgq_dconly(s,dest_y + 8*linesize + 8, linesize, dc[3]);
137 if(!(s->avctx->flags&CODEC_FLAG_GRAY)) {
138 tgq_dconly(s,dest_cb, s->frame.linesize[1], dc[4]);
139 tgq_dconly(s,dest_cr, s->frame.linesize[2], dc[5]);
143 static void tgq_decode_mb(TgqContext *s, int mb_y, int mb_x, const int8_t **bs, const int8_t *buf_end){
147 DCTELEM block[6][64];
149 mode = bytestream_get_byte((const uint8_t**)bs);
150 if (mode>buf_end-*bs) {
151 av_log(s->avctx, AV_LOG_ERROR, "truncated macroblock\n");
157 init_get_bits(&gb, *bs, mode*8);
159 tgq_decode_block(s, block[i], &gb);
160 tgq_idct_put_mb(s, block, mb_x, mb_y);
163 memset(dc, (*bs)[0], 4);
168 }else if (mode==12) {
172 av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
174 tgq_idct_put_mb_dconly(s, mb_x, mb_y, dc);
179 static void tgq_calculate_qtable(TgqContext *s, int quant){
181 const int a = (14*(100-quant))/100 + 1;
182 const int b = (11*(100-quant))/100 + 4;
185 if (s->avctx->idct_algo==FF_IDCT_EA)
186 s->qtable[j*8+i] = ((a*(j+i)/(7+7) + b)*ff_inv_aanscales[j*8+i])>>(14-4);
188 s->qtable[j*8+i] = (a*(j+i)/(7+7) + b)<<3;
191 static int tgq_decode_frame(AVCodecContext *avctx,
192 void *data, int *data_size,
193 const uint8_t *buf, int buf_size){
194 const uint8_t *buf_start = buf;
195 const uint8_t *buf_end = buf + buf_size;
196 TgqContext *s = avctx->priv_data;
199 int big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
203 av_log(avctx, AV_LOG_WARNING, "truncated header\n");
206 s->width = big_endian ? AV_RB16(&buf[0]) : AV_RL16(&buf[0]);
207 s->height = big_endian ? AV_RB16(&buf[2]) : AV_RL16(&buf[2]);
209 if (s->avctx->width!=s->width || s->avctx->height!=s->height) {
210 avcodec_set_dimensions(s->avctx, s->width, s->height);
211 if (s->frame.data[0])
212 avctx->release_buffer(avctx, &s->frame);
214 tgq_calculate_qtable(s, buf[4]);
217 if (!s->frame.data[0]) {
218 s->frame.key_frame = 1;
219 s->frame.pict_type = FF_I_TYPE;
220 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID;
221 if (avctx->get_buffer(avctx, &s->frame)) {
222 av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
227 for (y=0; y<(avctx->height+15)/16; y++)
228 for (x=0; x<(avctx->width+15)/16; x++)
229 tgq_decode_mb(s, y, x, (const int8_t**)&buf, (const int8_t*)buf_end);
231 *data_size = sizeof(AVFrame);
232 *(AVFrame*)data = s->frame;
234 return buf-buf_start;
237 static av_cold int tgq_decode_end(AVCodecContext *avctx){
238 TgqContext *s = avctx->priv_data;
239 if (s->frame.data[0])
240 s->avctx->release_buffer(avctx, &s->frame);
244 AVCodec eatgq_decoder = {
254 .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),