FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
eamad.c
Go to the documentation of this file.
1 /*
2  * Electronic Arts Madcow Video Decoder
3  * Copyright (c) 2007-2009 Peter Ross
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 Madcow Video Decoder
25  * @author Peter Ross <pross@xvid.org>
26  *
27  * @see technical details at
28  * http://wiki.multimedia.cx/index.php?title=Electronic_Arts_MAD
29  */
30 
31 #include "avcodec.h"
32 #include "blockdsp.h"
33 #include "bytestream.h"
34 #include "bswapdsp.h"
35 #include "get_bits.h"
36 #include "aandcttab.h"
37 #include "eaidct.h"
38 #include "idctdsp.h"
39 #include "internal.h"
40 #include "mpeg12data.h"
41 #include "mpeg12vlc.h"
42 
43 #define EA_PREAMBLE_SIZE 8
44 #define MADk_TAG MKTAG('M', 'A', 'D', 'k') /* MAD i-frame */
45 #define MADm_TAG MKTAG('M', 'A', 'D', 'm') /* MAD p-frame */
46 #define MADe_TAG MKTAG('M', 'A', 'D', 'e') /* MAD lqp-frame */
47 
48 typedef struct MadContext {
56  unsigned int bitstream_buf_size;
57  DECLARE_ALIGNED(16, int16_t, block)[64];
59  uint16_t quant_matrix[64];
60  int mb_x;
61  int mb_y;
62 } MadContext;
63 
65 {
66  MadContext *s = avctx->priv_data;
67  s->avctx = avctx;
68  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
69  ff_blockdsp_init(&s->bdsp, avctx);
71  ff_idctdsp_init(&s->idsp, avctx);
75 
77  if (!s->last_frame)
78  return AVERROR(ENOMEM);
79 
80  return 0;
81 }
82 
83 static inline void comp(unsigned char *dst, int dst_stride,
84  unsigned char *src, int src_stride, int add)
85 {
86  int j, i;
87  for (j=0; j<8; j++)
88  for (i=0; i<8; i++)
89  dst[j*dst_stride + i] = av_clip_uint8(src[j*src_stride + i] + add);
90 }
91 
92 static inline void comp_block(MadContext *t, AVFrame *frame,
93  int mb_x, int mb_y,
94  int j, int mv_x, int mv_y, int add)
95 {
96  if (j < 4) {
97  unsigned offset = (mb_y*16 + ((j&2)<<2) + mv_y)*t->last_frame->linesize[0] + mb_x*16 + ((j&1)<<3) + mv_x;
98  if (offset >= (t->avctx->height - 7) * t->last_frame->linesize[0] - 7)
99  return;
100  comp(frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
101  frame->linesize[0],
102  t->last_frame->data[0] + offset,
103  t->last_frame->linesize[0], add);
104  } else if (!(t->avctx->flags & AV_CODEC_FLAG_GRAY)) {
105  int index = j - 3;
106  unsigned offset = (mb_y * 8 + (mv_y/2))*t->last_frame->linesize[index] + mb_x * 8 + (mv_x/2);
107  if (offset >= (t->avctx->height/2 - 7) * t->last_frame->linesize[index] - 7)
108  return;
109  comp(frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x * 8,
110  frame->linesize[index],
111  t->last_frame->data[index] + offset,
112  t->last_frame->linesize[index], add);
113  }
114 }
115 
116 static inline void idct_put(MadContext *t, AVFrame *frame, int16_t *block,
117  int mb_x, int mb_y, int j)
118 {
119  if (j < 4) {
121  frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
122  frame->linesize[0], block);
123  } else if (!(t->avctx->flags & AV_CODEC_FLAG_GRAY)) {
124  int index = j - 3;
126  frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x*8,
127  frame->linesize[index], block);
128  }
129 }
130 
131 static inline int decode_block_intra(MadContext *s, int16_t * block)
132 {
133  int level, i, j, run;
134  RLTable *rl = &ff_rl_mpeg1;
135  const uint8_t *scantable = s->scantable.permutated;
136  int16_t *quant_matrix = s->quant_matrix;
137 
138  block[0] = (128 + get_sbits(&s->gb, 8)) * quant_matrix[0];
139 
140  /* The RL decoder is derived from mpeg1_decode_block_intra;
141  Escaped level and run values a decoded differently */
142  i = 0;
143  {
144  OPEN_READER(re, &s->gb);
145  /* now quantify & encode AC coefficients */
146  for (;;) {
147  UPDATE_CACHE(re, &s->gb);
148  GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
149 
150  if (level == 127) {
151  break;
152  } else if (level != 0) {
153  i += run;
154  if (i > 63) {
156  "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
157  return -1;
158  }
159  j = scantable[i];
160  level = (level*quant_matrix[j]) >> 4;
161  level = (level-1)|1;
162  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
163  LAST_SKIP_BITS(re, &s->gb, 1);
164  } else {
165  /* escape */
166  UPDATE_CACHE(re, &s->gb);
167  level = SHOW_SBITS(re, &s->gb, 10); SKIP_BITS(re, &s->gb, 10);
168 
169  UPDATE_CACHE(re, &s->gb);
170  run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
171 
172  i += run;
173  if (i > 63) {
175  "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
176  return -1;
177  }
178  j = scantable[i];
179  if (level < 0) {
180  level = -level;
181  level = (level*quant_matrix[j]) >> 4;
182  level = (level-1)|1;
183  level = -level;
184  } else {
185  level = (level*quant_matrix[j]) >> 4;
186  level = (level-1)|1;
187  }
188  }
189 
190  block[j] = level;
191  }
192  CLOSE_READER(re, &s->gb);
193  }
194  return 0;
195 }
196 
198 {
199  int value = 0;
200  if (get_bits1(gb)) {
201  if (get_bits1(gb))
202  value = -17;
203  value += get_bits(gb, 4) + 1;
204  }
205  return value;
206 }
207 
208 static int decode_mb(MadContext *s, AVFrame *frame, int inter)
209 {
210  int mv_map = 0;
211  int av_uninit(mv_x), av_uninit(mv_y);
212  int j;
213 
214  if (inter) {
215  int v = decode210(&s->gb);
216  if (v < 2) {
217  mv_map = v ? get_bits(&s->gb, 6) : 63;
218  mv_x = decode_motion(&s->gb);
219  mv_y = decode_motion(&s->gb);
220  }
221  }
222 
223  for (j=0; j<6; j++) {
224  if (mv_map & (1<<j)) { // mv_x and mv_y are guarded by mv_map
225  int add = 2*decode_motion(&s->gb);
226  if (s->last_frame->data[0])
227  comp_block(s, frame, s->mb_x, s->mb_y, j, mv_x, mv_y, add);
228  } else {
229  s->bdsp.clear_block(s->block);
230  if(decode_block_intra(s, s->block) < 0)
231  return -1;
232  idct_put(s, frame, s->block, s->mb_x, s->mb_y, j);
233  }
234  }
235  return 0;
236 }
237 
238 static void calc_quant_matrix(MadContext *s, int qscale)
239 {
240  int i;
241 
243  for (i=1; i<64; i++)
244  s->quant_matrix[i] = (ff_inv_aanscales[i]*ff_mpeg1_default_intra_matrix[i]*qscale + 32) >> 10;
245 }
246 
247 static int decode_frame(AVCodecContext *avctx,
248  void *data, int *got_frame,
249  AVPacket *avpkt)
250 {
251  const uint8_t *buf = avpkt->data;
252  int buf_size = avpkt->size;
253  MadContext *s = avctx->priv_data;
254  AVFrame *frame = data;
255  GetByteContext gb;
256  int width, height;
257  int chunk_type;
258  int inter, ret;
259 
260  bytestream2_init(&gb, buf, buf_size);
261 
262  chunk_type = bytestream2_get_le32(&gb);
263  inter = (chunk_type == MADm_TAG || chunk_type == MADe_TAG);
264  bytestream2_skip(&gb, 10);
265 
266  av_reduce(&avctx->framerate.den, &avctx->framerate.num,
267  bytestream2_get_le16(&gb), 1000, 1<<30);
268 
269  width = bytestream2_get_le16(&gb);
270  height = bytestream2_get_le16(&gb);
271  bytestream2_skip(&gb, 1);
272  calc_quant_matrix(s, bytestream2_get_byte(&gb));
273  bytestream2_skip(&gb, 2);
274 
275  if (bytestream2_get_bytes_left(&gb) < 2) {
276  av_log(avctx, AV_LOG_ERROR, "Input data too small\n");
277  return AVERROR_INVALIDDATA;
278  }
279 
280  if (width < 16 || height < 16) {
281  av_log(avctx, AV_LOG_ERROR, "Dimensions too small\n");
282  return AVERROR_INVALIDDATA;
283  }
284 
285  if (avctx->width != width || avctx->height != height) {
287  if((width * height)/2048*7 > bytestream2_get_bytes_left(&gb))
288  return AVERROR_INVALIDDATA;
289  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
290  return ret;
291  }
292 
293  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
294  return ret;
295 
296  if (inter && !s->last_frame->data[0]) {
297  av_log(avctx, AV_LOG_WARNING, "Missing reference frame.\n");
299  if (ret < 0)
300  return ret;
301  memset(s->last_frame->data[0], 0, s->last_frame->height *
302  s->last_frame->linesize[0]);
303  memset(s->last_frame->data[1], 0x80, s->last_frame->height / 2 *
304  s->last_frame->linesize[1]);
305  memset(s->last_frame->data[2], 0x80, s->last_frame->height / 2 *
306  s->last_frame->linesize[2]);
307  }
308 
311  if (!s->bitstream_buf)
312  return AVERROR(ENOMEM);
313  s->bbdsp.bswap16_buf(s->bitstream_buf, (const uint16_t *)(buf + bytestream2_tell(&gb)),
314  bytestream2_get_bytes_left(&gb) / 2);
317 
318  for (s->mb_y=0; s->mb_y < (avctx->height+15)/16; s->mb_y++)
319  for (s->mb_x=0; s->mb_x < (avctx->width +15)/16; s->mb_x++)
320  if(decode_mb(s, frame, inter) < 0)
321  return AVERROR_INVALIDDATA;
322 
323  *got_frame = 1;
324 
325  if (chunk_type != MADe_TAG) {
327  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
328  return ret;
329  }
330 
331  return buf_size;
332 }
333 
335 {
336  MadContext *t = avctx->priv_data;
338  av_freep(&t->bitstream_buf);
339  return 0;
340 }
341 
343  .name = "eamad",
344  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts Madcow Video"),
345  .type = AVMEDIA_TYPE_VIDEO,
346  .id = AV_CODEC_ID_MAD,
347  .priv_data_size = sizeof(MadContext),
348  .init = decode_init,
349  .close = decode_end,
350  .decode = decode_frame,
351  .capabilities = AV_CODEC_CAP_DR1,
352 };
AVRational framerate
Definition: avcodec.h:3303
float v
const char * s
Definition: avisynth_c.h:631
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:171
#define GET_RL_VLC
Definition: get_bits.h:689
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:101
void(* clear_block)(int16_t *block)
Definition: blockdsp.h:35
AVCodec ff_eamad_decoder
Definition: eamad.c:342
uint16_t quant_matrix[64]
Definition: eamad.c:59
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:260
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:182
av_cold void ff_mpeg12_init_vlcs(void)
Definition: mpeg12.c:145
static void comp_block(MadContext *t, AVFrame *frame, int mb_x, int mb_y, int j, int mv_x, int mv_y, int add)
Definition: eamad.c:92
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:216
void(* bswap16_buf)(uint16_t *dst, const uint16_t *src, int len)
Definition: bswapdsp.h:26
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
BlockDSPContext bdsp
Definition: eamad.c:50
Scantable.
Definition: idctdsp.h:29
MPEG1/2 VLC.
int num
numerator
Definition: rational.h:44
int size
Definition: avcodec.h:1423
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:53
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1721
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:133
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Same behaviour av_fast_malloc but the buffer has additional AV_INPUT_BUFFER_PADDING_SIZE at the end w...
Definition: utils.c:126
uint8_t permutated[64]
Definition: idctdsp.h:31
uint8_t run
Definition: svq3.c:149
AVCodec.
Definition: avcodec.h:3473
RLTable.
Definition: rl.h:38
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:245
uint8_t
#define av_cold
Definition: attributes.h:74
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:135
int av_frame_ref(AVFrame *dst, const AVFrame *src)
Set up a new reference to the data described by the source frame.
Definition: frame.c:363
static AVFrame * frame
uint8_t * data
Definition: avcodec.h:1422
bitstream reader API header.
#define AV_CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:762
static void calc_quant_matrix(MadContext *s, int qscale)
Definition: eamad.c:238
#define av_log(a,...)
AVCodecContext * avctx
Definition: eamad.c:49
IDCTDSPContext idsp
Definition: eamad.c:52
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:173
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:164
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:148
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:154
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1596
const char * name
Name of the codec implementation.
Definition: avcodec.h:3480
static av_cold int decode_end(AVCodecContext *avctx)
Definition: eamad.c:334
static int decode_block_intra(MadContext *s, int16_t *block)
Definition: eamad.c:131
static const uint8_t offset[127][2]
Definition: vf_spp.c:92
#define CLOSE_READER(name, gb)
Definition: get_bits.h:144
Libavcodec external API header.
#define SKIP_BITS(name, gb, num)
Definition: get_bits.h:188
int av_reduce(int *dst_num, int *dst_den, int64_t num, int64_t den, int64_t max)
Reduce a fraction.
Definition: rational.c:35
av_cold void ff_init_scantable_permutation(uint8_t *idct_permutation, enum idct_permutation_type perm_type)
Definition: idctdsp.c:50
ScanTable scantable
Definition: eamad.c:58
ret
Definition: avfilter.c:974
int width
picture width / height.
Definition: avcodec.h:1680
GLsizei GLboolean const GLfloat * value
Definition: opengl_enc.c:109
RLTable ff_rl_mpeg1
Definition: mpeg12data.c:166
int16_t block[64]
Definition: eamad.c:57
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: eamad.c:247
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:194
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:94
RL_VLC_ELEM * rl_vlc[32]
decoding only
Definition: rl.h:47
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:206
static int decode210(GetBitContext *gb)
Definition: get_bits.h:580
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:188
GetBitContext gb
Definition: eamad.c:54
#define MADe_TAG
Definition: eamad.c:46
AVS_Value src
Definition: avisynth_c.h:482
static void idct_put(MadContext *t, AVFrame *frame, int16_t *block, int mb_x, int mb_y, int j)
Definition: eamad.c:116
av_cold void ff_blockdsp_init(BlockDSPContext *c, AVCodecContext *avctx)
Definition: blockdsp.c:58
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:199
const uint16_t ff_inv_aanscales[64]
Definition: aandcttab.c:38
main external API structure.
Definition: avcodec.h:1501
MPEG1/2 tables.
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:1040
#define OPEN_READER(name, gb)
Definition: get_bits.h:133
static int decode_motion(GetBitContext *gb)
Definition: eamad.c:197
void * buf
Definition: avisynth_c.h:553
int mb_y
Definition: eamad.c:61
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:304
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
int index
Definition: gxfenc.c:89
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:410
const uint16_t ff_mpeg1_default_intra_matrix[256]
Definition: mpeg12data.c:30
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:117
BswapDSPContext bbdsp
Definition: eamad.c:51
void av_frame_unref(AVFrame *frame)
Unreference all the buffers referenced by frame and reset the frame fields.
Definition: frame.c:462
#define MADm_TAG
Definition: eamad.c:45
AAN (Arai, Agui and Nakajima) (I)DCT tables.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:182
uint8_t level
Definition: svq3.c:150
void ff_ea_idct_put_c(uint8_t *dest, int linesize, int16_t *block)
Definition: eaidct.c:80
static int decode(AVCodecContext *avctx, void *data, int *got_sub, AVPacket *avpkt)
Definition: ccaption_dec.c:522
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:207
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:63
common internal api header.
#define TEX_VLC_BITS
Definition: dv.h:93
void * bitstream_buf
Definition: eamad.c:55
int den
denominator
Definition: rational.h:45
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:635
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
void * priv_data
Definition: avcodec.h:1543
float re
Definition: fft-test.c:73
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
av_cold void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
Definition: idctdsp.c:241
static int decode_mb(MadContext *s, AVFrame *frame, int inter)
Definition: eamad.c:208
int mb_x
Definition: eamad.c:60
#define av_uninit(x)
Definition: attributes.h:141
int height
Definition: frame.h:220
#define av_freep(p)
static void comp(unsigned char *dst, int dst_stride, unsigned char *src, int src_stride, int add)
Definition: eamad.c:83
AVFrame * last_frame
Definition: eamad.c:53
unsigned int bitstream_buf_size
Definition: eamad.c:56
This structure stores compressed data.
Definition: avcodec.h:1399
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:1215
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:856
static av_cold int decode_init(AVCodecContext *avctx)
Definition: eamad.c:64
static int width
static int16_t block[64]
Definition: dct-test.c:110