FFmpeg
eatgq.c
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1 /*
2  * Electronic Arts TGQ Video Decoder
3  * Copyright (c) 2007-2008 Peter Ross <pross@xvid.org>
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 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 #define BITSTREAM_READER_LE
32 #include "aandcttab.h"
33 #include "avcodec.h"
34 #include "bytestream.h"
35 #include "eaidct.h"
36 #include "get_bits.h"
37 #include "idctdsp.h"
38 #include "internal.h"
39 
40 typedef struct TgqContext {
42  int width, height;
44  int qtable[64];
45  DECLARE_ALIGNED(16, int16_t, block)[6][64];
47 } TgqContext;
48 
50 {
51  TgqContext *s = avctx->priv_data;
52  uint8_t idct_permutation[64];
53  s->avctx = avctx;
55  ff_init_scantable(idct_permutation, &s->scantable, ff_zigzag_direct);
56  avctx->framerate = (AVRational){ 15, 1 };
57  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
58  return 0;
59 }
60 
61 static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
62 {
64  int i, j, value;
65  block[0] = get_sbits(gb, 8) * s->qtable[0];
66  for (i = 1; i < 64;) {
67  switch (show_bits(gb, 3)) {
68  case 4:
69  block[perm[i++]] = 0;
70  case 0:
71  block[perm[i++]] = 0;
72  skip_bits(gb, 3);
73  break;
74  case 5:
75  case 1:
76  skip_bits(gb, 2);
77  value = get_bits(gb, 6);
78  for (j = 0; j < value; j++)
79  block[perm[i++]] = 0;
80  break;
81  case 6:
82  skip_bits(gb, 3);
83  block[perm[i]] = -s->qtable[perm[i]];
84  i++;
85  break;
86  case 2:
87  skip_bits(gb, 3);
88  block[perm[i]] = s->qtable[perm[i]];
89  i++;
90  break;
91  case 7: // 111b
92  case 3: // 011b
93  skip_bits(gb, 2);
94  if (show_bits(gb, 6) == 0x3F) {
95  skip_bits(gb, 6);
96  block[perm[i]] = get_sbits(gb, 8) * s->qtable[perm[i]];
97  } else {
98  block[perm[i]] = get_sbits(gb, 6) * s->qtable[perm[i]];
99  }
100  i++;
101  break;
102  }
103  }
104  block[0] += 128 << 4;
105 }
106 
107 static void tgq_idct_put_mb(TgqContext *s, int16_t (*block)[64], AVFrame *frame,
108  int mb_x, int mb_y)
109 {
110  ptrdiff_t linesize = frame->linesize[0];
111  uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
112  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
113  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
114 
115  ff_ea_idct_put_c(dest_y , linesize, block[0]);
116  ff_ea_idct_put_c(dest_y + 8, linesize, block[1]);
117  ff_ea_idct_put_c(dest_y + 8 * linesize , linesize, block[2]);
118  ff_ea_idct_put_c(dest_y + 8 * linesize + 8, linesize, block[3]);
119  if (!(s->avctx->flags & AV_CODEC_FLAG_GRAY)) {
120  ff_ea_idct_put_c(dest_cb, frame->linesize[1], block[4]);
121  ff_ea_idct_put_c(dest_cr, frame->linesize[2], block[5]);
122  }
123 }
124 
125 static inline void tgq_dconly(TgqContext *s, unsigned char *dst,
126  ptrdiff_t dst_stride, int dc)
127 {
128  int level = av_clip_uint8((dc*s->qtable[0] + 2056) >> 4);
129  int j;
130  for (j = 0; j < 8; j++)
131  memset(dst + j * dst_stride, level, 8);
132 }
133 
135  int mb_x, int mb_y, const int8_t *dc)
136 {
137  ptrdiff_t linesize = frame->linesize[0];
138  uint8_t *dest_y = frame->data[0] + (mb_y * 16 * linesize) + mb_x * 16;
139  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
140  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * 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 & AV_CODEC_FLAG_GRAY)) {
146  tgq_dconly(s, dest_cb, frame->linesize[1], dc[4]);
147  tgq_dconly(s, dest_cr, frame->linesize[2], dc[5]);
148  }
149 }
150 
151 static int tgq_decode_mb(TgqContext *s, AVFrame *frame, 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) {
160  int ret = init_get_bits8(&gb, s->gb.buffer, FFMIN(bytestream2_get_bytes_left(&s->gb), mode));
161  if (ret < 0)
162  return ret;
163 
164  for (i = 0; i < 6; i++)
165  tgq_decode_block(s, s->block[i], &gb);
166  tgq_idct_put_mb(s, s->block, frame, mb_x, mb_y);
167  bytestream2_skip(&s->gb, mode);
168  } else {
169  if (mode == 3) {
170  memset(dc, bytestream2_get_byte(&s->gb), 4);
171  dc[4] = bytestream2_get_byte(&s->gb);
172  dc[5] = bytestream2_get_byte(&s->gb);
173  } else if (mode == 6) {
174  bytestream2_get_buffer(&s->gb, dc, 6);
175  } else if (mode == 12) {
176  for (i = 0; i < 6; i++) {
177  dc[i] = bytestream2_get_byte(&s->gb);
178  bytestream2_skip(&s->gb, 1);
179  }
180  } else {
181  av_log(s->avctx, AV_LOG_ERROR, "unsupported mb mode %i\n", mode);
182  return -1;
183  }
184  tgq_idct_put_mb_dconly(s, frame, mb_x, mb_y, dc);
185  }
186  return 0;
187 }
188 
190 {
191  int i, j;
192  const int a = (14 * (100 - quant)) / 100 + 1;
193  const int b = (11 * (100 - quant)) / 100 + 4;
194  for (j = 0; j < 8; j++)
195  for (i = 0; i < 8; i++)
196  s->qtable[j * 8 + i] = ((a * (j + i) / (7 + 7) + b) *
197  ff_inv_aanscales[j * 8 + i]) >> (14 - 4);
198 }
199 
201  void *data, int *got_frame,
202  AVPacket *avpkt)
203 {
204  const uint8_t *buf = avpkt->data;
205  int buf_size = avpkt->size;
206  TgqContext *s = avctx->priv_data;
207  AVFrame *frame = data;
208  int x, y, ret;
209  int big_endian;
210 
211  if (buf_size < 16) {
212  av_log(avctx, AV_LOG_WARNING, "truncated header\n");
213  return AVERROR_INVALIDDATA;
214  }
215  big_endian = AV_RL32(&buf[4]) > 0x000FFFFF;
216  bytestream2_init(&s->gb, buf + 8, buf_size - 8);
217  if (big_endian) {
218  s->width = bytestream2_get_be16u(&s->gb);
219  s->height = bytestream2_get_be16u(&s->gb);
220  } else {
221  s->width = bytestream2_get_le16u(&s->gb);
222  s->height = bytestream2_get_le16u(&s->gb);
223  }
224 
225  ret = ff_set_dimensions(s->avctx, s->width, s->height);
226  if (ret < 0)
227  return ret;
228 
229  tgq_calculate_qtable(s, bytestream2_get_byteu(&s->gb));
230  bytestream2_skip(&s->gb, 3);
231 
232  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
233  return ret;
234  frame->key_frame = 1;
235  frame->pict_type = AV_PICTURE_TYPE_I;
236 
237  for (y = 0; y < FFALIGN(avctx->height, 16) >> 4; y++)
238  for (x = 0; x < FFALIGN(avctx->width, 16) >> 4; x++)
239  if (tgq_decode_mb(s, frame, y, x) < 0)
240  return AVERROR_INVALIDDATA;
241 
242  *got_frame = 1;
243 
244  return avpkt->size;
245 }
246 
248  .name = "eatgq",
249  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts TGQ video"),
250  .type = AVMEDIA_TYPE_VIDEO,
251  .id = AV_CODEC_ID_TGQ,
252  .priv_data_size = sizeof(TgqContext),
255  .capabilities = AV_CODEC_CAP_DR1,
256 };
AVRational framerate
Definition: avcodec.h:3108
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
int height
Definition: eatgq.c:42
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static void tgq_idct_put_mb(TgqContext *s, int16_t(*block)[64], AVFrame *frame, int mb_x, int mb_y)
Definition: eatgq.c:107
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:379
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
Scantable.
Definition: idctdsp.h:31
int size
Definition: avcodec.h:1481
static void tgq_idct_put_mb_dconly(TgqContext *s, AVFrame *frame, int mb_x, int mb_y, const int8_t *dc)
Definition: eatgq.c:134
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1778
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
uint8_t permutated[64]
Definition: idctdsp.h:33
AVCodec.
Definition: avcodec.h:3492
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:359
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
static av_cold int tgq_decode_init(AVCodecContext *avctx)
Definition: eatgq.c:49
uint8_t
#define av_cold
Definition: attributes.h:82
static void tgq_decode_block(TgqContext *s, int16_t block[64], GetBitContext *gb)
Definition: eatgq.c:61
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:108
GetByteContext gb
Definition: eatgq.c:46
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:112
uint8_t * data
Definition: avcodec.h:1480
const uint8_t * buffer
Definition: bytestream.h:34
bitstream reader API header.
void ff_ea_idct_put_c(uint8_t *dest, ptrdiff_t linesize, int16_t *block)
Definition: eaidct.c:80
#define AV_CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:886
#define FFALIGN(x, a)
Definition: macros.h:48
#define av_log(a,...)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size)
Definition: bytestream.h:263
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1648
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
ScanTable scantable
Definition: eatgq.c:43
#define b
Definition: input.c:41
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:378
#define FFMIN(a, b)
Definition: common.h:96
av_cold void ff_init_scantable_permutation(uint8_t *idct_permutation, enum idct_permutation_type perm_type)
Definition: idctdsp.c:50
int width
picture width / height.
Definition: avcodec.h:1741
static void tgq_dconly(TgqContext *s, unsigned char *dst, ptrdiff_t dst_stride, int dc)
Definition: eatgq.c:125
static unsigned int show_bits(GetBitContext *s, int n)
Show 1-25 bits.
Definition: get_bits.h:446
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
perm
Definition: f_perms.c:74
#define s(width, name)
Definition: cbs_vp9.c:257
static int tgq_decode_mb(TgqContext *s, AVFrame *frame, int mb_y, int mb_x)
Definition: eatgq.c:151
AVCodec ff_eatgq_decoder
Definition: eatgq.c:247
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:326
const uint16_t ff_inv_aanscales[64]
Definition: aandcttab.c:38
static int init_get_bits8(GetBitContext *s, const uint8_t *buffer, int byte_size)
Initialize GetBitContext.
Definition: get_bits.h:677
main external API structure.
Definition: avcodec.h:1568
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2]...the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so...,+,-,+,-,+,+,-,+,-,+,...hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32-hcoeff[1]-hcoeff[2]-...a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2}an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||.........intra?||||:Block01:yes no||||:Block02:.................||||:Block03::y DC::ref index:||||:Block04::cb DC::motion x:||||.........:cr DC::motion y:||||.................|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------------------------------|||Y subbands||Cb subbands||Cr subbands||||------||------||------|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||------||------||------||||------||------||------|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||------||------||------||||------||------||------|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||------||------||------||||------||------||------|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------------------------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction------------|\Dequantization-------------------\||Reference frames|\IDWT|--------------|Motion\|||Frame 0||Frame 1||Compensation.OBMC v-------|--------------|--------------.\------> Frame n output Frame Frame<----------------------------------/|...|-------------------Range Coder:============Binary Range Coder:-------------------The implemented range coder is an adapted version based upon"Range encoding: an algorithm for removing redundancy from a digitised message."by G.N.N.Martin.The symbols encoded by the Snow range coder are bits(0|1).The associated probabilities are not fix but change depending on the symbol mix seen so far.bit seen|new state---------+-----------------------------------------------0|256-state_transition_table[256-old_state];1|state_transition_table[old_state];state_transition_table={0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:-------------------------FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1.the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled top and top right vectors is used as motion vector prediction the used motion vector is the sum of the predictor and(mvx_diff, mvy_diff)*mv_scale Intra DC Prediction block[y][x] dc[1]
Definition: snow.txt:400
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1968
void * buf
Definition: avisynth_c.h:766
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:467
Rational number (pair of numerator and denominator).
Definition: rational.h:58
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:98
int qtable[64]
Definition: eatgq.c:44
const uint8_t * quant
AAN (Arai, Agui and Nakajima) (I)DCT tables.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
int width
Definition: eatgq.c:42
uint8_t level
Definition: svq3.c:207
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
common internal api header.
void * priv_data
Definition: avcodec.h:1595
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
int16_t block[6][64]
Definition: eatgq.c:45
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:373
static void tgq_calculate_qtable(TgqContext *s, int quant)
Definition: eatgq.c:189
static int tgq_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eatgq.c:200
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_RL32
Definition: bytestream.h:87
This structure stores compressed data.
Definition: avcodec.h:1457
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:984
AVCodecContext * avctx
Definition: eatgq.c:41