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dnxhddec.c
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1 /*
2  * VC3/DNxHD decoder.
3  * Copyright (c) 2007 SmartJog S.A., Baptiste Coudurier <baptiste dot coudurier at smartjog dot com>
4  * Copyright (c) 2011 MirriAd Ltd
5  *
6  * 10 bit support added by MirriAd Ltd, Joseph Artsimovich <joseph@mirriad.com>
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 //#define TRACE
26 //#define DEBUG
27 
28 #include "libavutil/imgutils.h"
29 #include "avcodec.h"
30 #include "get_bits.h"
31 #include "dnxhddata.h"
32 #include "dsputil.h"
33 #include "internal.h"
34 #include "thread.h"
35 
36 typedef struct DNXHDContext {
40  int64_t cid; ///< compression id
41  unsigned int width, height;
42  unsigned int mb_width, mb_height;
43  uint32_t mb_scan_index[68]; /* max for 1080p */
44  int cur_field; ///< current interlaced field
46  int last_dc[3];
51  int bit_depth; // 8, 10 or 0 if not initialized at all.
53  int n, int qscale);
55  int luma_scale[64];
56  int chroma_scale[64];
57 } DNXHDContext;
58 
59 #define DNXHD_VLC_BITS 9
60 #define DNXHD_DC_VLC_BITS 7
61 
62 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, DCTELEM *block, int n, int qscale);
63 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, DCTELEM *block, int n, int qscale);
64 
66 {
67  DNXHDContext *ctx = avctx->priv_data;
68 
69  ctx->avctx = avctx;
70  avctx->coded_frame = &ctx->picture;
73  ctx->picture.key_frame = 1;
74  ctx->cid = -1;
75  return 0;
76 }
77 
78 static int dnxhd_init_vlc(DNXHDContext *ctx, uint32_t cid)
79 {
80  if (cid != ctx->cid) {
81  int index;
82 
83  if ((index = ff_dnxhd_get_cid_table(cid)) < 0) {
84  av_log(ctx->avctx, AV_LOG_ERROR, "unsupported cid %d\n", cid);
85  return -1;
86  }
87  if (ff_dnxhd_cid_table[index].bit_depth != ctx->bit_depth) {
88  av_log(ctx->avctx, AV_LOG_ERROR, "bit depth mismatches %d %d\n", ff_dnxhd_cid_table[index].bit_depth, ctx->bit_depth);
89  return AVERROR_INVALIDDATA;
90  }
92 
93  ff_free_vlc(&ctx->ac_vlc);
94  ff_free_vlc(&ctx->dc_vlc);
95  ff_free_vlc(&ctx->run_vlc);
96 
97  init_vlc(&ctx->ac_vlc, DNXHD_VLC_BITS, 257,
98  ctx->cid_table->ac_bits, 1, 1,
99  ctx->cid_table->ac_codes, 2, 2, 0);
100  init_vlc(&ctx->dc_vlc, DNXHD_DC_VLC_BITS, ctx->bit_depth + 4,
101  ctx->cid_table->dc_bits, 1, 1,
102  ctx->cid_table->dc_codes, 1, 1, 0);
103  init_vlc(&ctx->run_vlc, DNXHD_VLC_BITS, 62,
104  ctx->cid_table->run_bits, 1, 1,
105  ctx->cid_table->run_codes, 2, 2, 0);
106 
108  ctx->cid = cid;
109  }
110  return 0;
111 }
112 
113 static int dnxhd_decode_header(DNXHDContext *ctx, const uint8_t *buf, int buf_size, int first_field)
114 {
115  static const uint8_t header_prefix[] = { 0x00, 0x00, 0x02, 0x80, 0x01 };
116  int i, cid;
117 
118  if (buf_size < 0x280)
119  return -1;
120 
121  if (memcmp(buf, header_prefix, 5)) {
122  av_log(ctx->avctx, AV_LOG_ERROR, "error in header\n");
123  return -1;
124  }
125  if (buf[5] & 2) { /* interlaced */
126  ctx->cur_field = buf[5] & 1;
127  ctx->picture.interlaced_frame = 1;
128  ctx->picture.top_field_first = first_field ^ ctx->cur_field;
129  av_log(ctx->avctx, AV_LOG_DEBUG, "interlaced %d, cur field %d\n", buf[5] & 3, ctx->cur_field);
130  }
131 
132  ctx->height = AV_RB16(buf + 0x18);
133  ctx->width = AV_RB16(buf + 0x1a);
134 
135  av_dlog(ctx->avctx, "width %d, height %d\n", ctx->width, ctx->height);
136 
137  if (buf[0x21] & 0x40) {
139  ctx->avctx->bits_per_raw_sample = 10;
140  if (ctx->bit_depth != 10) {
141  ff_dsputil_init(&ctx->dsp, ctx->avctx);
142  ctx->bit_depth = 10;
144  }
145  } else {
147  ctx->avctx->bits_per_raw_sample = 8;
148  if (ctx->bit_depth != 8) {
149  ff_dsputil_init(&ctx->dsp, ctx->avctx);
150  ctx->bit_depth = 8;
152  }
153  }
154 
155  cid = AV_RB32(buf + 0x28);
156  av_dlog(ctx->avctx, "compression id %d\n", cid);
157 
158  if (dnxhd_init_vlc(ctx, cid) < 0)
159  return -1;
160 
161  if (buf_size < ctx->cid_table->coding_unit_size) {
162  av_log(ctx->avctx, AV_LOG_ERROR, "incorrect frame size\n");
163  return -1;
164  }
165 
166  ctx->mb_width = ctx->width>>4;
167  ctx->mb_height = buf[0x16d];
168 
169  av_dlog(ctx->avctx, "mb width %d, mb height %d\n", ctx->mb_width, ctx->mb_height);
170 
171  if ((ctx->height+15)>>4 == ctx->mb_height && ctx->picture.interlaced_frame)
172  ctx->height <<= 1;
173 
174  if (ctx->mb_height > 68 ||
175  (ctx->mb_height<<ctx->picture.interlaced_frame) > (ctx->height+15)>>4) {
176  av_log(ctx->avctx, AV_LOG_ERROR, "mb height too big: %d\n", ctx->mb_height);
177  return -1;
178  }
179 
180  for (i = 0; i < ctx->mb_height; i++) {
181  ctx->mb_scan_index[i] = AV_RB32(buf + 0x170 + (i<<2));
182  av_dlog(ctx->avctx, "mb scan index %d\n", ctx->mb_scan_index[i]);
183  if (buf_size < ctx->mb_scan_index[i] + 0x280) {
184  av_log(ctx->avctx, AV_LOG_ERROR, "invalid mb scan index\n");
185  return -1;
186  }
187  }
188 
189  return 0;
190 }
191 
193  DCTELEM *block, int n,
194  int qscale,
195  int index_bits,
196  int level_bias,
197  int level_shift)
198 {
199  int i, j, index1, index2, len, flags;
200  int level, component, sign;
201  const int *scale;
202  const uint8_t *weight_matrix;
203  const uint8_t *ac_level = ctx->cid_table->ac_level;
204  const uint8_t *ac_flags = ctx->cid_table->ac_flags;
205  const int eob_index = ctx->cid_table->eob_index;
206  OPEN_READER(bs, &ctx->gb);
207 
208  if (n&2) {
209  component = 1 + (n&1);
210  scale = ctx->chroma_scale;
211  weight_matrix = ctx->cid_table->chroma_weight;
212  } else {
213  component = 0;
214  scale = ctx->luma_scale;
215  weight_matrix = ctx->cid_table->luma_weight;
216  }
217 
218  UPDATE_CACHE(bs, &ctx->gb);
219  GET_VLC(len, bs, &ctx->gb, ctx->dc_vlc.table, DNXHD_DC_VLC_BITS, 1);
220  if (len) {
221  level = GET_CACHE(bs, &ctx->gb);
222  LAST_SKIP_BITS(bs, &ctx->gb, len);
223  sign = ~level >> 31;
224  level = (NEG_USR32(sign ^ level, len) ^ sign) - sign;
225  ctx->last_dc[component] += level;
226  }
227  block[0] = ctx->last_dc[component];
228 
229  i = 0;
230 
231  UPDATE_CACHE(bs, &ctx->gb);
232  GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
233  DNXHD_VLC_BITS, 2);
234 
235  while (index1 != eob_index) {
236  level = ac_level[index1];
237  flags = ac_flags[index1];
238 
239  sign = SHOW_SBITS(bs, &ctx->gb, 1);
240  SKIP_BITS(bs, &ctx->gb, 1);
241 
242  if (flags & 1) {
243  level += SHOW_UBITS(bs, &ctx->gb, index_bits) << 7;
244  SKIP_BITS(bs, &ctx->gb, index_bits);
245  }
246 
247  if (flags & 2) {
248  UPDATE_CACHE(bs, &ctx->gb);
249  GET_VLC(index2, bs, &ctx->gb, ctx->run_vlc.table,
250  DNXHD_VLC_BITS, 2);
251  i += ctx->cid_table->run[index2];
252  }
253 
254  if (++i > 63) {
255  av_log(ctx->avctx, AV_LOG_ERROR, "ac tex damaged %d, %d\n", n, i);
256  break;
257  }
258 
259  j = ctx->scantable.permutated[i];
260  level *= scale[i];
261  if (level_bias < 32 || weight_matrix[i] != level_bias)
262  level += level_bias;
263  level >>= level_shift;
264 
265  block[j] = (level^sign) - sign;
266 
267  UPDATE_CACHE(bs, &ctx->gb);
268  GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
269  DNXHD_VLC_BITS, 2);
270  }
271 
272  CLOSE_READER(bs, &ctx->gb);
273 }
274 
276  int n, int qscale)
277 {
278  dnxhd_decode_dct_block(ctx, block, n, qscale, 4, 32, 6);
279 }
280 
282  int n, int qscale)
283 {
284  dnxhd_decode_dct_block(ctx, block, n, qscale, 6, 8, 4);
285 }
286 
287 static int dnxhd_decode_macroblock(DNXHDContext *ctx, int x, int y)
288 {
289  int shift1 = ctx->bit_depth == 10;
290  int dct_linesize_luma = ctx->picture.linesize[0];
291  int dct_linesize_chroma = ctx->picture.linesize[1];
292  uint8_t *dest_y, *dest_u, *dest_v;
293  int dct_y_offset, dct_x_offset;
294  int qscale, i;
295 
296  qscale = get_bits(&ctx->gb, 11);
297  skip_bits1(&ctx->gb);
298 
299  if (qscale != ctx->last_qscale) {
300  for (i = 0; i < 64; i++) {
301  ctx->luma_scale[i] = qscale * ctx->cid_table->luma_weight[i];
302  ctx->chroma_scale[i] = qscale * ctx->cid_table->chroma_weight[i];
303  }
304  ctx->last_qscale = qscale;
305  }
306 
307  for (i = 0; i < 8; i++) {
308  ctx->dsp.clear_block(ctx->blocks[i]);
309  ctx->decode_dct_block(ctx, ctx->blocks[i], i, qscale);
310  }
311 
312  if (ctx->picture.interlaced_frame) {
313  dct_linesize_luma <<= 1;
314  dct_linesize_chroma <<= 1;
315  }
316 
317  dest_y = ctx->picture.data[0] + ((y * dct_linesize_luma) << 4) + (x << (4 + shift1));
318  dest_u = ctx->picture.data[1] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1));
319  dest_v = ctx->picture.data[2] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1));
320 
321  if (ctx->cur_field) {
322  dest_y += ctx->picture.linesize[0];
323  dest_u += ctx->picture.linesize[1];
324  dest_v += ctx->picture.linesize[2];
325  }
326 
327  dct_y_offset = dct_linesize_luma << 3;
328  dct_x_offset = 8 << shift1;
329  ctx->dsp.idct_put(dest_y, dct_linesize_luma, ctx->blocks[0]);
330  ctx->dsp.idct_put(dest_y + dct_x_offset, dct_linesize_luma, ctx->blocks[1]);
331  ctx->dsp.idct_put(dest_y + dct_y_offset, dct_linesize_luma, ctx->blocks[4]);
332  ctx->dsp.idct_put(dest_y + dct_y_offset + dct_x_offset, dct_linesize_luma, ctx->blocks[5]);
333 
334  if (!(ctx->avctx->flags & CODEC_FLAG_GRAY)) {
335  dct_y_offset = dct_linesize_chroma << 3;
336  ctx->dsp.idct_put(dest_u, dct_linesize_chroma, ctx->blocks[2]);
337  ctx->dsp.idct_put(dest_v, dct_linesize_chroma, ctx->blocks[3]);
338  ctx->dsp.idct_put(dest_u + dct_y_offset, dct_linesize_chroma, ctx->blocks[6]);
339  ctx->dsp.idct_put(dest_v + dct_y_offset, dct_linesize_chroma, ctx->blocks[7]);
340  }
341 
342  return 0;
343 }
344 
345 static int dnxhd_decode_macroblocks(DNXHDContext *ctx, const uint8_t *buf, int buf_size)
346 {
347  int x, y;
348  for (y = 0; y < ctx->mb_height; y++) {
349  ctx->last_dc[0] =
350  ctx->last_dc[1] =
351  ctx->last_dc[2] = 1 << (ctx->bit_depth + 2); // for levels +2^(bitdepth-1)
352  init_get_bits(&ctx->gb, buf + ctx->mb_scan_index[y], (buf_size - ctx->mb_scan_index[y]) << 3);
353  for (x = 0; x < ctx->mb_width; x++) {
354  //START_TIMER;
355  dnxhd_decode_macroblock(ctx, x, y);
356  //STOP_TIMER("decode macroblock");
357  }
358  }
359  return 0;
360 }
361 
362 static int dnxhd_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
363  AVPacket *avpkt)
364 {
365  const uint8_t *buf = avpkt->data;
366  int buf_size = avpkt->size;
367  DNXHDContext *ctx = avctx->priv_data;
368  AVFrame *picture = data;
369  int first_field = 1;
370  int ret;
371 
372  av_dlog(avctx, "frame size %d\n", buf_size);
373 
374  decode_coding_unit:
375  if (dnxhd_decode_header(ctx, buf, buf_size, first_field) < 0)
376  return -1;
377 
378  if ((avctx->width || avctx->height) &&
379  (ctx->width != avctx->width || ctx->height != avctx->height)) {
380  av_log(avctx, AV_LOG_WARNING, "frame size changed: %dx%d -> %dx%d\n",
381  avctx->width, avctx->height, ctx->width, ctx->height);
382  first_field = 1;
383  }
384 
385  if (av_image_check_size(ctx->width, ctx->height, 0, avctx))
386  return -1;
387  avcodec_set_dimensions(avctx, ctx->width, ctx->height);
388 
389  if (first_field) {
390  if (ctx->picture.data[0])
391  ff_thread_release_buffer(avctx, &ctx->picture);
392  if ((ret = ff_thread_get_buffer(avctx, &ctx->picture)) < 0) {
393  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
394  return ret;
395  }
396  }
397 
398  dnxhd_decode_macroblocks(ctx, buf + 0x280, buf_size - 0x280);
399 
400  if (first_field && ctx->picture.interlaced_frame) {
401  buf += ctx->cid_table->coding_unit_size;
402  buf_size -= ctx->cid_table->coding_unit_size;
403  first_field = 0;
404  goto decode_coding_unit;
405  }
406 
407  *picture = ctx->picture;
408  *got_frame = 1;
409  return avpkt->size;
410 }
411 
413 {
414  DNXHDContext *ctx = avctx->priv_data;
415 
416  if (ctx->picture.data[0])
417  ff_thread_release_buffer(avctx, &ctx->picture);
418  ff_free_vlc(&ctx->ac_vlc);
419  ff_free_vlc(&ctx->dc_vlc);
420  ff_free_vlc(&ctx->run_vlc);
421  return 0;
422 }
423 
425  .name = "dnxhd",
426  .type = AVMEDIA_TYPE_VIDEO,
427  .id = AV_CODEC_ID_DNXHD,
428  .priv_data_size = sizeof(DNXHDContext),
432  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
433  .long_name = NULL_IF_CONFIG_SMALL("VC3/DNxHD"),
434 };