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 "mpegvideo.h"
34 #include "mpeg12.h"
35 #include "thread.h"
36 
37 typedef struct MDECContext {
44  int version;
45  int qscale;
46  int last_dc[3];
47  int mb_width;
48  int mb_height;
49  int mb_x, mb_y;
50  DECLARE_ALIGNED(16, int16_t, block)[6][64];
52  unsigned int bitstream_buffer_size;
54 } MDECContext;
55 
56 //very similar to MPEG-1
57 static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
58 {
59  int level, diff, i, j, run;
60  int component;
61  RLTable *rl = &ff_rl_mpeg1;
62  uint8_t * const scantable = a->scantable.permutated;
63  const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
64  const int qscale = a->qscale;
65 
66  /* DC coefficient */
67  if (a->version == 2) {
68  block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
69  } else {
70  component = (n <= 3 ? 0 : n - 4 + 1);
71  diff = decode_dc(&a->gb, component);
72  if (diff >= 0xffff)
73  return AVERROR_INVALIDDATA;
74  a->last_dc[component] += diff;
75  block[0] = a->last_dc[component] << 3;
76  }
77 
78  i = 0;
79  {
80  OPEN_READER(re, &a->gb);
81  /* now quantify & encode AC coefficients */
82  for (;;) {
83  UPDATE_CACHE(re, &a->gb);
84  GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
85 
86  if (level == 127) {
87  break;
88  } else if (level != 0) {
89  i += run;
90  j = scantable[i];
91  level = (level * qscale * quant_matrix[j]) >> 3;
92  level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
93  LAST_SKIP_BITS(re, &a->gb, 1);
94  } else {
95  /* escape */
96  run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
97  UPDATE_CACHE(re, &a->gb);
98  level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
99  i += run;
100  j = scantable[i];
101  if (level < 0) {
102  level = -level;
103  level = (level * qscale * quant_matrix[j]) >> 3;
104  level = (level - 1) | 1;
105  level = -level;
106  } else {
107  level = (level * qscale * quant_matrix[j]) >> 3;
108  level = (level - 1) | 1;
109  }
110  }
111  if (i > 63) {
112  av_log(a->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
113  return AVERROR_INVALIDDATA;
114  }
115 
116  block[j] = level;
117  }
118  CLOSE_READER(re, &a->gb);
119  }
120  a->block_last_index[n] = i;
121  return 0;
122 }
123 
124 static inline int decode_mb(MDECContext *a, int16_t block[6][64])
125 {
126  int i, ret;
127  const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
128 
129  a->bdsp.clear_blocks(block[0]);
130 
131  for (i = 0; i < 6; i++) {
132  if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
133  block_index[i])) < 0)
134  return ret;
135  if (get_bits_left(&a->gb) < 0)
136  return AVERROR_INVALIDDATA;
137  }
138  return 0;
139 }
140 
141 static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
142 {
143  int16_t (*block)[64] = a->block;
144  int linesize = frame->linesize[0];
145 
146  uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
147  uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
148  uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
149 
150  a->idsp.idct_put(dest_y, linesize, block[0]);
151  a->idsp.idct_put(dest_y + 8, linesize, block[1]);
152  a->idsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
153  a->idsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
154 
155  if (!(a->avctx->flags & CODEC_FLAG_GRAY)) {
156  a->idsp.idct_put(dest_cb, frame->linesize[1], block[4]);
157  a->idsp.idct_put(dest_cr, frame->linesize[2], block[5]);
158  }
159 }
160 
161 static int decode_frame(AVCodecContext *avctx,
162  void *data, int *got_frame,
163  AVPacket *avpkt)
164 {
165  MDECContext * const a = avctx->priv_data;
166  const uint8_t *buf = avpkt->data;
167  int buf_size = avpkt->size;
168  ThreadFrame frame = { .f = data };
169  int i, ret;
170 
171  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0) {
172  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
173  return ret;
174  }
175  frame.f->pict_type = AV_PICTURE_TYPE_I;
176  frame.f->key_frame = 1;
177 
179  if (!a->bitstream_buffer)
180  return AVERROR(ENOMEM);
181  for (i = 0; i < buf_size; i += 2) {
182  a->bitstream_buffer[i] = buf[i + 1];
183  a->bitstream_buffer[i + 1] = buf[i];
184  }
185  init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
186 
187  /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
188  skip_bits(&a->gb, 32);
189 
190  a->qscale = get_bits(&a->gb, 16);
191  a->version = get_bits(&a->gb, 16);
192 
193  a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
194 
195  for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
196  for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
197  if ((ret = decode_mb(a, a->block)) < 0)
198  return ret;
199 
200  idct_put(a, frame.f, a->mb_x, a->mb_y);
201  }
202  }
203 
204  *got_frame = 1;
205 
206  return (get_bits_count(&a->gb) + 31) / 32 * 4;
207 }
208 
210 {
211  MDECContext * const a = avctx->priv_data;
212 
213  a->mb_width = (avctx->coded_width + 15) / 16;
214  a->mb_height = (avctx->coded_height + 15) / 16;
215 
216  a->avctx = avctx;
217 
218  ff_blockdsp_init(&a->bdsp, avctx);
219  ff_idctdsp_init(&a->idsp, avctx);
223 
224  if (avctx->idct_algo == FF_IDCT_AUTO)
225  avctx->idct_algo = FF_IDCT_SIMPLE;
226  avctx->pix_fmt = AV_PIX_FMT_YUVJ420P;
227  avctx->color_range = AVCOL_RANGE_JPEG;
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:124
AVCodecContext * avctx
Definition: mdec.c:38
#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
int coded_width
Bitstream width / height, may be different from width/height e.g.
Definition: avcodec.h:1234
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:138
AVFrame * f
Definition: thread.h:36
#define FF_IDCT_SIMPLE
Definition: avcodec.h:2476
ThreadFrame frame
Definition: mdec.c:41
int mb_x
Definition: mdec.c:49
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:1766
Scantable.
Definition: idctdsp.h:29
int size
Definition: avcodec.h:974
void(* clear_blocks)(int16_t *blocks)
Definition: blockdsp.h:36
GetBitContext gb
Definition: mdec.c:42
#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
mpegvideo header.
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
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:275
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:161
#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
int mb_width
Definition: mdec.c:47
static int get_bits_count(const GetBitContext *s)
Definition: get_bits.h:194
int block_last_index[6]
Definition: mdec.c:53
#define FF_IDCT_AUTO
Definition: avcodec.h:2474
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:45
#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:150
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
int16_t block[6][64]
Definition: mdec.c:50
#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:190
#define FF_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:531
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:196
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of PIX_FMT_YUV420P and setting color_...
Definition: pixfmt.h:77
int idct_algo
IDCT algorithm, see FF_IDCT_* below.
Definition: avcodec.h:2473
RLTable ff_rl_mpeg1
Definition: mpeg12data.c:166
int mb_height
Definition: mdec.c:48
unsigned int bitstream_buffer_size
Definition: mdec.c:52
#define LAST_SKIP_BITS(name, gb, num)
Definition: get_bits.h:182
uint8_t * bitstream_buffer
Definition: mdec.c:51
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
the normal 2^n-1 "JPEG" YUV ranges
Definition: pixfmt.h:365
void(* idct_put)(uint8_t *dest, int line_size, int16_t *block)
block -> idct -> clip to unsigned 8 bit -> dest.
Definition: idctdsp.h:70
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:153
IDCTDSPContext idsp
Definition: mdec.c:40
int ff_thread_get_buffer(AVCodecContext *avctx, ThreadFrame *f, int flags)
Wrapper around get_buffer() for frame-multithreaded codecs.
ScanTable scantable
Definition: mdec.c:43
main external API structure.
Definition: avcodec.h:1050
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:490
#define OPEN_READER(name, gb)
Definition: get_bits.h:127
static av_cold int decode_end(AVCodecContext *avctx)
Definition: mdec.c:241
static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
Definition: mdec.c:232
int coded_height
Definition: avcodec.h:1234
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:57
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
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:141
uint8_t level
Definition: svq3.c:147
BlockDSPContext bdsp
Definition: mdec.c:39
#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:388
#define CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: avcodec.h:755
#define TEX_VLC_BITS
Definition: dv.h:97
#define CODEC_FLAG_GRAY
Only decode/encode grayscale.
Definition: avcodec.h:637
int mb_y
Definition: mdec.c:49
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 key_frame
1 -> keyframe, 0-> not
Definition: frame.h:191
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:141
static av_cold int decode_init(AVCodecContext *avctx)
Definition: mdec.c:209
This structure stores compressed data.
Definition: avcodec.h:950
int last_dc[3]
Definition: mdec.c:46
int version
Definition: mdec.c:44
static int16_t block[64]
Definition: dct-test.c:88