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"),