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 "mpegvideo.h"
32 #include "mpeg12.h"
33 #include "thread.h"
34 
35 typedef struct MDECContext {
41  int version;
42  int qscale;
43  int last_dc[3];
44  int mb_width;
45  int mb_height;
46  int mb_x, mb_y;
47  DECLARE_ALIGNED(16, int16_t, block)[6][64];
49  unsigned int bitstream_buffer_size;
51 } MDECContext;
52 
53 //very similar to MPEG-1
54 static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
55 {
56  int level, diff, i, j, run;
57  int component;
58  RLTable *rl = &ff_rl_mpeg1;
59  uint8_t * const scantable = a->scantable.permutated;
60  const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
61  const int qscale = a->qscale;
62 
63  /* DC coefficient */
64  if (a->version == 2) {
65  block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
66  } else {
67  component = (n <= 3 ? 0 : n - 4 + 1);
68  diff = decode_dc(&a->gb, component);
69  if (diff >= 0xffff)
70  return AVERROR_INVALIDDATA;
71  a->last_dc[component] += diff;
72  block[0] = a->last_dc[component] << 3;
73  }
74 
75  i = 0;
76  {
77  OPEN_READER(re, &a->gb);
78  /* now quantify & encode AC coefficients */
79  for (;;) {
80  UPDATE_CACHE(re, &a->gb);
81  GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
82 
83  if (level == 127) {
84  break;
85  } else if (level != 0) {
86  i += run;
87  if (i > 63) {
89  "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
90  return AVERROR_INVALIDDATA;
91  }
92  j = scantable[i];
93  level = (level * qscale * quant_matrix[j]) >> 3;
94  level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
95  LAST_SKIP_BITS(re, &a->gb, 1);
96  } else {
97  /* escape */
98  run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
99  UPDATE_CACHE(re, &a->gb);
100  level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
101  i += run;
102  if (i > 63) {
104  "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
105  return AVERROR_INVALIDDATA;
106  }
107  j = scantable[i];
108  if (level < 0) {
109  level = -level;
110  level = (level * qscale * quant_matrix[j]) >> 3;
111  level = (level - 1) | 1;
112  level = -level;
113  } else {
114  level = (level * qscale * quant_matrix[j]) >> 3;
115  level = (level - 1) | 1;
116  }
117  }
118 
119  block[j] = level;
120  }
121  CLOSE_READER(re, &a->gb);
122  }
123  a->block_last_index[n] = i;
124  return 0;
125 }
126 
127 static inline int decode_mb(MDECContext *a, int16_t block[6][64])
128 {
129  int i, ret;
130  const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
131 
132  a->dsp.clear_blocks(block[0]);
133 
134  for (i = 0; i < 6; i++) {
135  if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
136  block_index[i])) < 0)
137  return ret;
138  if (get_bits_left(&a->gb) < 0)
139  return AVERROR_INVALIDDATA;
140  }
141  return 0;
142 }
143 
144 static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
145 {
146  int16_t (*block)[64] = a->block;
147  int linesize = frame->linesize[0];
148 
149  uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
150  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
151  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
152 
153  a->dsp.idct_put(dest_y, linesize, block[0]);
154  a->dsp.idct_put(dest_y + 8, linesize, block[1]);
155  a->dsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
156  a->dsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
157 
158  if (!(a->avctx->flags & CODEC_FLAG_GRAY)) {
159  a->dsp.idct_put(dest_cb, frame->linesize[1], block[4]);
160  a->dsp.idct_put(dest_cr, frame->linesize[2], block[5]);
161  }
162 }
163 
164 static int decode_frame(AVCodecContext *avctx,
165  void *data, int *got_frame,
166  AVPacket *avpkt)
167 {
168  MDECContext * const a = avctx->priv_data;
169  const uint8_t *buf = avpkt->data;
170  int buf_size = avpkt->size;
171  ThreadFrame frame = { .f = data };
172  int i, ret;
173 
174  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0) {
175  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
176  return ret;
177  }
178  frame.f->pict_type = AV_PICTURE_TYPE_I;
179  frame.f->key_frame = 1;
180 
182  if (!a->bitstream_buffer)
183  return AVERROR(ENOMEM);
184  for (i = 0; i < buf_size; i += 2) {
185  a->bitstream_buffer[i] = buf[i + 1];
186  a->bitstream_buffer[i + 1] = buf[i];
187  }
188  init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
189 
190  /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
191  skip_bits(&a->gb, 32);
192 
193  a->qscale = get_bits(&a->gb, 16);
194  a->version = get_bits(&a->gb, 16);
195 
196  a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
197 
198  for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
199  for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
200  if ((ret = decode_mb(a, a->block)) < 0)
201  return ret;
202 
203  idct_put(a, frame.f, a->mb_x, a->mb_y);
204  }
205  }
206 
207  *got_frame = 1;
208 
209  return (get_bits_count(&a->gb) + 31) / 32 * 4;
210 }
211 
213 {
214  MDECContext * const a = avctx->priv_data;
215 
216  a->mb_width = (avctx->coded_width + 15) / 16;
217  a->mb_height = (avctx->coded_height + 15) / 16;
218 
219  a->avctx = avctx;
220 
221  ff_dsputil_init(&a->dsp, avctx);
224 
225  if (avctx->idct_algo == FF_IDCT_AUTO)
226  avctx->idct_algo = FF_IDCT_SIMPLE;
227  avctx->pix_fmt = AV_PIX_FMT_YUVJ420P;
228 
229  return 0;
230 }
231 
233 {
234  MDECContext * const a = avctx->priv_data;
235 
236  a->avctx = avctx;
237 
238  return 0;
239 }
240 
242 {
243  MDECContext * const a = avctx->priv_data;
244 
246  a->bitstream_buffer_size = 0;
247 
248  return 0;
249 }
250 
252  .name = "mdec",
253  .long_name = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
254  .type = AVMEDIA_TYPE_VIDEO,
255  .id = AV_CODEC_ID_MDEC,
256  .priv_data_size = sizeof(MDECContext),
257  .init = decode_init,
258  .close = decode_end,
259  .decode = decode_frame,
260  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
262 };
static int decode_mb(MDECContext *a, int16_t block[6][64])
Definition: mdec.c:127
av_cold void ff_dsputil_init(DSPContext *c, AVCodecContext *avctx)
Definition: dsputil.c:2440
AVCodecContext * avctx
Definition: mdec.c:36
#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:107
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:1227
DSPContext dsp
Definition: mdec.c:37
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition: get_bits.h:240
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:2459
ThreadFrame frame
Definition: mdec.c:38
int mb_x
Definition: mdec.c:46
Scantable.
Definition: dsputil.h:111
int size
Definition: avcodec.h:974
GetBitContext gb
Definition: mdec.c:39
#define DECLARE_ALIGNED(n, t, v)
Definition: mem.h:58
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1247
mpegvideo header.
uint8_t permutated[64]
Definition: dsputil.h:113
uint8_t run
Definition: svq3.c:142
AVCodec.
Definition: avcodec.h:2755
RLTable.
Definition: rl.h:38
static int get_sbits(GetBitContext *s, int n)
Definition: get_bits.h:226
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:198
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:269
void(* idct_put)(uint8_t *dest, int line_size, int16_t *block)
block -> idct -> clip to unsigned 8 bit -> dest.
Definition: dsputil.h:220
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:164
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:711
const char data[16]
Definition: mxf.c:66
uint8_t * data
Definition: avcodec.h:973
int mb_width
Definition: mdec.c:44
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:194
uint8_t idct_permutation[64]
idct input permutation.
Definition: dsputil.h:240
int block_last_index[6]
Definition: mdec.c:50
#define FF_IDCT_AUTO
Definition: avcodec.h:2457
const uint16_t ff_mpeg1_default_intra_matrix[64]
Definition: mpeg12data.c:30
static int get_bits_left(GetBitContext *gb)
Definition: get_bits.h:555
#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
int qscale
Definition: mdec.c:42
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:142
int flags
CODEC_FLAG_*.
Definition: avcodec.h:1142
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:148
const char * name
Name of the codec implementation.
Definition: avcodec.h:2762
int16_t block[6][64]
Definition: mdec.c:47
#define CLOSE_READER(name, gb)
Definition: get_bits.h:141
static int decode_dc(GetBitContext *gb, int component)
Definition: mpeg12.h:49
#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
#define ONLY_IF_THREADS_ENABLED(x)
Define a function with only the non-default version specified.
Definition: internal.h:182
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:509
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:168
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of PIX_FMT_YUV420P and setting color_...
Definition: pixfmt.h:77
void(* clear_blocks)(int16_t *blocks)
Definition: dsputil.h:143
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:2456
RLTable ff_rl_mpeg1
Definition: mpeg12data.c:166
int mb_height
Definition: mdec.c:45
unsigned int bitstream_buffer_size
Definition: mdec.c:49
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:182
uint8_t * bitstream_buffer
Definition: mdec.c:48
RL_VLC_ELEM * rl_vlc[32]
decoding only
Definition: rl.h:48
#define SHOW_UBITS(name, gb, num)
Definition: get_bits.h:188
Libavcodec external API header.
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:125
int ff_thread_get_buffer(AVCodecContext *avctx, ThreadFrame *f, int flags)
Wrapper around get_buffer() for frame-multithreaded codecs.
ScanTable scantable
Definition: mdec.c:40
main external API structure.
Definition: avcodec.h:1054
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:489
#define OPEN_READER(name, gb)
Definition: get_bits.h:127
static av_cold int decode_end(AVCodecContext *avctx)
Definition: mdec.c:241
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: dsputil.c:107
static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
Definition: mdec.c:232
int coded_height
Definition: avcodec.h:1227
static void skip_bits(GetBitContext *s, int n)
Definition: get_bits.h:263
static int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
Definition: mdec.c:54
static int init_get_bits(GetBitContext *s, const uint8_t *buffer, int bit_size)
Initialize GetBitContext.
Definition: get_bits.h:375
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:113
uint8_t level
Definition: svq3.c:143
#define SHOW_SBITS(name, gb, num)
Definition: get_bits.h:189
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:368
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:113
#define CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: avcodec.h:782
#define TEX_VLC_BITS
Definition: dv.h:90
#define CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:670
int mb_y
Definition: mdec.c:46
static av_cold int init(AVCodecParserContext *s)
Definition: h264_parser.c:498
void * priv_data
Definition: avcodec.h:1090
float re
Definition: fft-test.c:65
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:163
AVCodec ff_mdec_decoder
Definition: mdec.c:251
static void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
Definition: mdec.c:144
static av_cold int decode_init(AVCodecContext *avctx)
Definition: mdec.c:212
This structure stores compressed data.
Definition: avcodec.h:950
int last_dc[3]
Definition: mdec.c:43
DSPContext.
Definition: dsputil.h:124
int version
Definition: mdec.c:41
static int16_t block[64]
Definition: dct-test.c:170