Libav
mdec.c
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1 /*
2  * Sony PlayStation MDEC (Motion DECoder)
3  * Copyright (c) 2003 Michael Niedermayer
4  *
5  * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
6  *
7  * This file is part of Libav.
8  *
9  * Libav is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU Lesser General Public
11  * License as published by the Free Software Foundation; either
12  * version 2.1 of the License, or (at your option) any later version.
13  *
14  * Libav is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17  * Lesser General Public License for more details.
18  *
19  * You should have received a copy of the GNU Lesser General Public
20  * License along with Libav; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  */
23 
30 #include "avcodec.h"
31 #include "blockdsp.h"
32 #include "idctdsp.h"
33 #include "mpeg12.h"
34 #include "thread.h"
35 
36 typedef struct MDECContext {
43  int version;
44  int qscale;
45  int last_dc[3];
46  int mb_width;
47  int mb_height;
48  int mb_x, mb_y;
49  DECLARE_ALIGNED(16, int16_t, block)[6][64];
51  unsigned int bitstream_buffer_size;
53 } MDECContext;
54 
55 //very similar to MPEG-1
56 static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
57 {
58  int level, diff, i, j, run;
59  int component;
60  RLTable *rl = &ff_rl_mpeg1;
62  const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
63  const int qscale = a->qscale;
64 
65  /* DC coefficient */
66  if (a->version == 2) {
67  block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
68  } else {
69  component = (n <= 3 ? 0 : n - 4 + 1);
70  diff = decode_dc(&a->gb, component);
71  if (diff >= 0xffff)
72  return AVERROR_INVALIDDATA;
73  a->last_dc[component] += diff;
74  block[0] = a->last_dc[component] << 3;
75  }
76 
77  i = 0;
78  {
79  OPEN_READER(re, &a->gb);
80  /* now quantify & encode AC coefficients */
81  for (;;) {
82  UPDATE_CACHE(re, &a->gb);
83  GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
84 
85  if (level == 127) {
86  break;
87  } else if (level != 0) {
88  i += run;
89  if (i > 63) {
91  "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
92  return AVERROR_INVALIDDATA;
93  }
94  j = scantable[i];
95  level = (level * qscale * quant_matrix[j]) >> 3;
96  level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
97  LAST_SKIP_BITS(re, &a->gb, 1);
98  } else {
99  /* escape */
100  run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
101  UPDATE_CACHE(re, &a->gb);
102  level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
103  i += run;
104  if (i > 63) {
106  "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
107  return AVERROR_INVALIDDATA;
108  }
109  j = scantable[i];
110  if (level < 0) {
111  level = -level;
112  level = (level * qscale * quant_matrix[j]) >> 3;
113  level = (level - 1) | 1;
114  level = -level;
115  } else {
116  level = (level * qscale * quant_matrix[j]) >> 3;
117  level = (level - 1) | 1;
118  }
119  }
120 
121  block[j] = level;
122  }
123  CLOSE_READER(re, &a->gb);
124  }
125  a->block_last_index[n] = i;
126  return 0;
127 }
128 
129 static inline int decode_mb(MDECContext *a, int16_t block[6][64])
130 {
131  int i, ret;
132  static const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
133 
134  a->bdsp.clear_blocks(block[0]);
135 
136  for (i = 0; i < 6; i++) {
137  if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
138  block_index[i])) < 0)
139  return ret;
140  if (get_bits_left(&a->gb) < 0)
141  return AVERROR_INVALIDDATA;
142  }
143  return 0;
144 }
145 
146 static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
147 {
148  int16_t (*block)[64] = a->block;
149  int linesize = frame->linesize[0];
150 
151  uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
152  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
153  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
154 
155  a->idsp.idct_put(dest_y, linesize, block[0]);
156  a->idsp.idct_put(dest_y + 8, linesize, block[1]);
157  a->idsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
158  a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
159 
160  if (!(a->avctx->flags & AV_CODEC_FLAG_GRAY)) {
161  a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);
162  a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);
163  }
164 }
165 
167  void *data, int *got_frame,
168  AVPacket *avpkt)
169 {
170  MDECContext * const a = avctx->priv_data;
171  const uint8_t *buf = avpkt->data;
172  int buf_size = avpkt->size;
173  ThreadFrame frame = { .f = data };
174  int i, ret;
175 
176  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0) {
177  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
178  return ret;
179  }
180  frame.f->pict_type = AV_PICTURE_TYPE_I;
181  frame.f->key_frame = 1;
182 
184  if (!a->bitstream_buffer)
185  return AVERROR(ENOMEM);
186  for (i = 0; i < buf_size; i += 2) {
187  a->bitstream_buffer[i] = buf[i + 1];
188  a->bitstream_buffer[i + 1] = buf[i];
189  }
190  init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
191 
192  /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
193  skip_bits(&a->gb, 32);
194 
195  a->qscale = get_bits(&a->gb, 16);
196  a->version = get_bits(&a->gb, 16);
197 
198  a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
199 
200  for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
201  for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
202  if ((ret = decode_mb(a, a->block)) < 0)
203  return ret;
204 
205  idct_put(a, frame.f, a->mb_x, a->mb_y);
206  }
207  }
208 
209  *got_frame = 1;
210 
211  return (get_bits_count(&a->gb) + 31) / 32 * 4;
212 }
213 
215 {
216  MDECContext * const a = avctx->priv_data;
217 
218  a->mb_width = (avctx->coded_width + 15) / 16;
219  a->mb_height = (avctx->coded_height + 15) / 16;
220 
221  a->avctx = avctx;
222 
223  ff_blockdsp_init(&a->bdsp, avctx);
224  ff_idctdsp_init(&a->idsp, avctx);
228 
229  if (avctx->idct_algo == FF_IDCT_AUTO)
230  avctx->idct_algo = FF_IDCT_SIMPLE;
231  avctx->pix_fmt = AV_PIX_FMT_YUVJ420P;
232  avctx->color_range = AVCOL_RANGE_JPEG;
233 
234  return 0;
235 }
236 
238 {
239  MDECContext * const a = avctx->priv_data;
240 
241  a->avctx = avctx;
242 
243  return 0;
244 }
245 
247 {
248  MDECContext * const a = avctx->priv_data;
249 
251  a->bitstream_buffer_size = 0;
252 
253  return 0;
254 }
255 
257  .name = "mdec",
258  .long_name = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
259  .type = AVMEDIA_TYPE_VIDEO,
260  .id = AV_CODEC_ID_MDEC,
261  .priv_data_size = sizeof(MDECContext),
262  .init = decode_init,
263  .close = decode_end,
264  .decode = decode_frame,
267 };
static int decode_mb(MDECContext *a, int16_t block[6][64])
Definition: mdec.c:129
AVCodecContext * avctx
Definition: mdec.c:37
#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:140
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:1595
float re
Definition: fft.c:69
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:228
av_cold void ff_mpeg12_init_vlcs(void)
Definition: mpeg12.c:139
AVFrame * f
Definition: thread.h:36
#define FF_IDCT_SIMPLE
Definition: avcodec.h:2738
ThreadFrame frame
Definition: mdec.c:40
int mb_x
Definition: mdec.c:48
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:2127
Scantable.
Definition: idctdsp.h:29
int size
Definition: avcodec.h:1347
av_log(ac->avr, AV_LOG_TRACE, "%d samples - audio_convert: %s to %s (%s)\, len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic ? ac->func_descr_generic :ac->func_descr)
GetBitContext gb
Definition: mdec.c:41
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:58
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1621
uint8_t permutated[64]
Definition: idctdsp.h:31
uint8_t run
Definition: svq3.c:203
AVCodec.
Definition: avcodec.h:3120
RLTable.
Definition: rl.h:39
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:214
void av_freep(void *arg)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc() and set the pointer ...
Definition: mem.c:202
uint8_t
#define av_cold
Definition: attributes.h:66
Multithreading support functions.
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: mdec.c:166
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:1346
int mb_width
Definition: mdec.c:46
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:182
int block_last_index[6]
Definition: mdec.c:52
#define AV_CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:763
#define FF_IDCT_AUTO
Definition: avcodec.h:2736
const uint16_t ff_mpeg1_default_intra_matrix[64]
Definition: mpeg12data.c:30
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:526
#define UPDATE_CACHE(name, gb)
Definition: get_bits.h:149
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:124
int qscale
Definition: mdec.c:44
#define AVERROR(e)
Definition: error.h:43
void(* clear_blocks)(int16_t *blocks)
Definition: blockdsp.h:36
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:148
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:1503
const char * name
Name of the codec implementation.
Definition: avcodec.h:3127
int16_t block[6][64]
Definition: mdec.c:49
#define CLOSE_READER(name, gb)
Definition: get_bits.h:129
static int decode_dc(GetBitContext *gb, int component)
Definition: mpeg12.h:32
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: avcodec.h:893
#define SKIP_BITS(name, gb, num)
Definition: get_bits.h:164
#define ONLY_IF_THREADS_ENABLED(x)
Define a function with only the non-default version specified.
Definition: internal.h:188
void(* idct_put)(uint8_t *dest, int line_size, int16_t *block)
block -> idct -> clip to unsigned 8 bit -> dest.
Definition: idctdsp.h:70
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:201
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:71
static int decode(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *pkt)
Definition: avconv.c:1288
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:2735
#define GET_RL_VLC(level, run, name, gb, table, bits, max_depth, need_update)
Definition: get_bits.h:448
RLTable ff_rl_mpeg1
Definition: mpeg12data.c:166
int mb_height
Definition: mdec.c:47
unsigned int bitstream_buffer_size
Definition: mdec.c:51
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:170
uint8_t * bitstream_buffer
Definition: mdec.c:50
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:94
RL_VLC_ELEM * rl_vlc[32]
decoding only
Definition: rl.h:49
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:176
the normal 2^n-1 "JPEG" YUV ranges
Definition: pixfmt.h:365
Libavcodec external API header.
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:158
IDCTDSPContext idsp
Definition: mdec.c:39
int ff_thread_get_buffer(AVCodecContext *avctx, ThreadFrame *f, int flags)
Wrapper around get_buffer() for frame-multithreaded codecs.
ScanTable scantable
Definition: mdec.c:42
main external API structure.
Definition: avcodec.h:1409
#define OPEN_READER(name, gb)
Definition: get_bits.h:118
static av_cold int decode_end(AVCodecContext *avctx)
Definition: mdec.c:246
static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
Definition: mdec.c:237
int coded_height
Definition: avcodec.h:1595
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:259
static int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
Definition: mdec.c:56
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:362
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:115
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:146
uint8_t level
Definition: svq3.c:204
BlockDSPContext bdsp
Definition: mdec.c:38
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:177
void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
Allocate a buffer, reusing the given one if large enough.
Definition: mem.c:394
#define TEX_VLC_BITS
Definition: dv.h:97
int mb_y
Definition: mdec.c:48
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:582
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:638
void * priv_data
Definition: avcodec.h:1451
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:147
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:196
AVCodec ff_mdec_decoder
Definition: mdec.c:256
static void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
Definition: mdec.c:146
static av_cold int decode_init(AVCodecContext *avctx)
Definition: mdec.c:214
This structure stores compressed data.
Definition: avcodec.h:1323
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:838
int last_dc[3]
Definition: mdec.c:45
int version
Definition: mdec.c:43