Libav
eamad.c
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1 /*
2  * Electronic Arts Madcow Video Decoder
3  * Copyright (c) 2007-2009 Peter Ross
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 
31 #include "avcodec.h"
32 #include "bytestream.h"
33 #include "bswapdsp.h"
34 #include "get_bits.h"
35 #include "aandcttab.h"
36 #include "eaidct.h"
37 #include "idctdsp.h"
38 #include "internal.h"
39 #include "mpeg12.h"
40 #include "mpeg12data.h"
41 #include "libavutil/imgutils.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  comp(frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
98  frame->linesize[0],
99  t->last_frame->data[0] + (mb_y*16 + ((j&2)<<2) + mv_y)*t->last_frame->linesize[0] + mb_x*16 + ((j&1)<<3) + mv_x,
100  t->last_frame->linesize[0], add);
101  } else if (!(t->avctx->flags & CODEC_FLAG_GRAY)) {
102  int index = j - 3;
103  comp(frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x * 8,
104  frame->linesize[index],
105  t->last_frame->data[index] + (mb_y * 8 + (mv_y/2))*t->last_frame->linesize[index] + mb_x * 8 + (mv_x/2),
106  t->last_frame->linesize[index], add);
107  }
108 }
109 
110 static inline void idct_put(MadContext *t, AVFrame *frame, int16_t *block,
111  int mb_x, int mb_y, int j)
112 {
113  if (j < 4) {
115  frame->data[0] + (mb_y*16 + ((j&2)<<2))*frame->linesize[0] + mb_x*16 + ((j&1)<<3),
116  frame->linesize[0], block);
117  } else if (!(t->avctx->flags & CODEC_FLAG_GRAY)) {
118  int index = j - 3;
120  frame->data[index] + (mb_y*8)*frame->linesize[index] + mb_x*8,
121  frame->linesize[index], block);
122  }
123 }
124 
125 static inline void decode_block_intra(MadContext *s, int16_t * block)
126 {
127  int level, i, j, run;
128  RLTable *rl = &ff_rl_mpeg1;
129  const uint8_t *scantable = s->scantable.permutated;
130  int16_t *quant_matrix = s->quant_matrix;
131 
132  block[0] = (128 + get_sbits(&s->gb, 8)) * quant_matrix[0];
133 
134  /* The RL decoder is derived from mpeg1_decode_block_intra;
135  Escaped level and run values a decoded differently */
136  i = 0;
137  {
138  OPEN_READER(re, &s->gb);
139  /* now quantify & encode AC coefficients */
140  for (;;) {
141  UPDATE_CACHE(re, &s->gb);
142  GET_RL_VLC(level, run, re, &s->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
143 
144  if (level == 127) {
145  break;
146  } else if (level != 0) {
147  i += run;
148  j = scantable[i];
149  level = (level*quant_matrix[j]) >> 4;
150  level = (level-1)|1;
151  level = (level ^ SHOW_SBITS(re, &s->gb, 1)) - SHOW_SBITS(re, &s->gb, 1);
152  LAST_SKIP_BITS(re, &s->gb, 1);
153  } else {
154  /* escape */
155  UPDATE_CACHE(re, &s->gb);
156  level = SHOW_SBITS(re, &s->gb, 10); SKIP_BITS(re, &s->gb, 10);
157 
158  UPDATE_CACHE(re, &s->gb);
159  run = SHOW_UBITS(re, &s->gb, 6)+1; LAST_SKIP_BITS(re, &s->gb, 6);
160 
161  i += run;
162  j = scantable[i];
163  if (level < 0) {
164  level = -level;
165  level = (level*quant_matrix[j]) >> 4;
166  level = (level-1)|1;
167  level = -level;
168  } else {
169  level = (level*quant_matrix[j]) >> 4;
170  level = (level-1)|1;
171  }
172  }
173  if (i > 63) {
174  av_log(s->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", s->mb_x, s->mb_y);
175  return;
176  }
177 
178  block[j] = level;
179  }
180  CLOSE_READER(re, &s->gb);
181  }
182 }
183 
185 {
186  int value = 0;
187  if (get_bits1(gb)) {
188  if (get_bits1(gb))
189  value = -17;
190  value += get_bits(gb, 4) + 1;
191  }
192  return value;
193 }
194 
195 static void decode_mb(MadContext *s, AVFrame *frame, int inter)
196 {
197  int mv_map = 0;
198  int mv_x, mv_y;
199  int j;
200 
201  if (inter) {
202  int v = decode210(&s->gb);
203  if (v < 2) {
204  mv_map = v ? get_bits(&s->gb, 6) : 63;
205  mv_x = decode_motion(&s->gb);
206  mv_y = decode_motion(&s->gb);
207  } else {
208  mv_map = 0;
209  }
210  }
211 
212  for (j=0; j<6; j++) {
213  if (mv_map & (1<<j)) { // mv_x and mv_y are guarded by mv_map
214  int add = 2*decode_motion(&s->gb);
215  comp_block(s, frame, s->mb_x, s->mb_y, j, mv_x, mv_y, add);
216  } else {
217  s->bdsp.clear_block(s->block);
218  decode_block_intra(s, s->block);
219  idct_put(s, frame, s->block, s->mb_x, s->mb_y, j);
220  }
221  }
222 }
223 
224 static void calc_quant_matrix(MadContext *s, int qscale)
225 {
226  int i;
227 
229  for (i=1; i<64; i++)
230  s->quant_matrix[i] = (ff_inv_aanscales[i]*ff_mpeg1_default_intra_matrix[i]*qscale + 32) >> 10;
231 }
232 
233 static int decode_frame(AVCodecContext *avctx,
234  void *data, int *got_frame,
235  AVPacket *avpkt)
236 {
237  const uint8_t *buf = avpkt->data;
238  int buf_size = avpkt->size;
239  MadContext *s = avctx->priv_data;
240  AVFrame *frame = data;
241  GetByteContext gb;
242  int width, height;
243  int chunk_type;
244  int inter, ret;
245 
246  bytestream2_init(&gb, buf, buf_size);
247 
248  chunk_type = bytestream2_get_le32(&gb);
249  inter = (chunk_type == MADm_TAG || chunk_type == MADe_TAG);
250  bytestream2_skip(&gb, 10);
251 
252  av_reduce(&avctx->time_base.num, &avctx->time_base.den,
253  bytestream2_get_le16(&gb), 1000, 1<<30);
254 
255  width = bytestream2_get_le16(&gb);
256  height = bytestream2_get_le16(&gb);
257  bytestream2_skip(&gb, 1);
258  calc_quant_matrix(s, bytestream2_get_byte(&gb));
259  bytestream2_skip(&gb, 2);
260 
261  if (bytestream2_get_bytes_left(&gb) < 2) {
262  av_log(avctx, AV_LOG_ERROR, "Input data too small\n");
263  return AVERROR_INVALIDDATA;
264  }
265 
266  if (avctx->width != width || avctx->height != height) {
268  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
269  return ret;
270  }
271 
272  if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) {
273  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
274  return ret;
275  }
276 
277  if (inter && !s->last_frame->data[0]) {
278  av_log(avctx, AV_LOG_WARNING, "Missing reference frame.\n");
280  if (ret < 0)
281  return ret;
282  memset(s->last_frame->data[0], 0, s->last_frame->height *
283  s->last_frame->linesize[0]);
284  memset(s->last_frame->data[1], 0x80, s->last_frame->height / 2 *
285  s->last_frame->linesize[1]);
286  memset(s->last_frame->data[2], 0x80, s->last_frame->height / 2 *
287  s->last_frame->linesize[2]);
288  }
289 
292  if (!s->bitstream_buf)
293  return AVERROR(ENOMEM);
294  s->bbdsp.bswap16_buf(s->bitstream_buf, (const uint16_t *)(buf + bytestream2_tell(&gb)),
295  bytestream2_get_bytes_left(&gb) / 2);
297 
298  for (s->mb_y=0; s->mb_y < (avctx->height+15)/16; s->mb_y++)
299  for (s->mb_x=0; s->mb_x < (avctx->width +15)/16; s->mb_x++)
300  decode_mb(s, frame, inter);
301 
302  *got_frame = 1;
303 
304  if (chunk_type != MADe_TAG) {
306  if ((ret = av_frame_ref(s->last_frame, frame)) < 0)
307  return ret;
308  }
309 
310  return buf_size;
311 }
312 
314 {
315  MadContext *t = avctx->priv_data;
318  return 0;
319 }
320 
322  .name = "eamad",
323  .long_name = NULL_IF_CONFIG_SMALL("Electronic Arts Madcow Video"),
324  .type = AVMEDIA_TYPE_VIDEO,
325  .id = AV_CODEC_ID_MAD,
326  .priv_data_size = sizeof(MadContext),
327  .init = decode_init,
328  .close = decode_end,
329  .decode = decode_frame,
330  .capabilities = CODEC_CAP_DR1,
331 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
void(* clear_block)(int16_t *block)
Definition: blockdsp.h:35
AVCodec ff_eamad_decoder
Definition: eamad.c:321
uint16_t quant_matrix[64]
Definition: eamad.c:59
misc image utilities
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:240
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:129
av_cold void ff_mpeg12_init_vlcs(void)
Definition: mpeg12.c:138
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:133
void(* bswap16_buf)(uint16_t *dst, const uint16_t *src, int len)
Definition: bswapdsp.h:26
BlockDSPContext bdsp
Definition: eamad.c:50
Scantable.
Definition: idctdsp.h:29
int num
numerator
Definition: rational.h:44
int size
Definition: avcodec.h:974
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:58
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1254
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:130
void av_fast_padded_malloc(void *ptr, unsigned int *size, size_t min_size)
Allocate a buffer with padding, reusing the given one if large enough.
Definition: utils.c:59
uint8_t permutated[64]
Definition: idctdsp.h:31
uint8_t run
Definition: svq3.c:146
AVCodec.
Definition: avcodec.h:2796
RLTable.
Definition: rl.h:38
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:226
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1175
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
uint8_t
#define av_cold
Definition: attributes.h:66
static void decode_block_intra(MadContext *s, int16_t *block)
Definition: eamad.c:125
AVFrame * av_frame_alloc(void)
Allocate an AVFrame and set its fields to default values.
Definition: frame.c:57
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:188
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
bitstream reader API header.
static void decode_mb(MadContext *s, AVFrame *frame, int inter)
Definition: eamad.c:195
static void calc_quant_matrix(MadContext *s, int qscale)
Definition: eamad.c:224
AVCodecContext * avctx
Definition: eamad.c:49
IDCTDSPContext idsp
Definition: eamad.c:52
const uint16_t ff_mpeg1_default_intra_matrix[64]
Definition: mpeg12data.c:30
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:161
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:186
#define AVERROR(e)
Definition: error.h:43
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:159
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:69
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:150
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:149
int flags
CODEC_FLAG_*.
Definition: avcodec.h:1144
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:168
const char * name
Name of the codec implementation.
Definition: avcodec.h:2803
static av_cold int decode_end(AVCodecContext *avctx)
Definition: eamad.c:313
#define CLOSE_READER(name, gb)
Definition: get_bits.h:141
#define GET_RL_VLC(level, run, name, gb, table, bits,max_depth, need_update)
Definition: get_bits.h:488
#define SKIP_BITS(name, gb, num)
Definition: get_bits.h:176
av_cold void ff_bswapdsp_init(BswapDSPContext *c)
Definition: bswapdsp.c:49
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:49
ScanTable scantable
Definition: eamad.c:58
int width
picture width / height.
Definition: avcodec.h:1224
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:233
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:182
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:94
RL_VLC_ELEM * rl_vlc[32]
decoding only
Definition: rl.h:48
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:188
static int decode210(GetBitContext *gb)
Definition: get_bits.h:547
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:183
GetBitContext gb
Definition: eamad.c:54
#define MADe_TAG
Definition: eamad.c:46
static int width
Definition: utils.c:156
Libavcodec external API header.
static void idct_put(MadContext *t, AVFrame *frame, int16_t *block, int mb_x, int mb_y, int j)
Definition: eamad.c:110
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:153
const uint16_t ff_inv_aanscales[64]
Definition: aandcttab.c:38
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
MPEG1/2 tables.
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:612
#define OPEN_READER(name, gb)
Definition: get_bits.h:127
static int decode_motion(GetBitContext *gb)
Definition: eamad.c:184
int mb_y
Definition: eamad.c:61
static unsigned int get_bits1(GetBitContext *s)
Definition: get_bits.h:271
int index
Definition: gxfenc.c:72
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:375
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:115
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:283
#define MADm_TAG
Definition: eamad.c:45
AAN (Arai Agui Nakajima) (I)DCT tables.
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
uint8_t level
Definition: svq3.c:147
int height
Definition: gxfenc.c:72
void ff_ea_idct_put_c(uint8_t *dest, int linesize, int16_t *block)
Definition: eaidct.c:80
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:189
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:65
common internal api header.
#define TEX_VLC_BITS
Definition: dv.h:97
#define CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:637
void * bitstream_buf
Definition: eamad.c:55
int den
denominator
Definition: rational.h:45
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:499
void * priv_data
Definition: avcodec.h:1092
float re
Definition: fft-test.c:69
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:28
av_cold void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
Definition: idctdsp.c:156
int mb_x
Definition: eamad.c:60
int height
Definition: frame.h:174
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:950
#define AV_GET_BUFFER_FLAG_REF
The decoder will keep a reference to the frame and may reuse it later.
Definition: avcodec.h:850
static av_cold int decode_init(AVCodecContext *avctx)
Definition: eamad.c:64
static int16_t block[64]
Definition: dct-test.c:88