Libav
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 Libav.
9  *
10  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #include "libavutil/imgutils.h"
26 #include "libavutil/timer.h"
27 #include "avcodec.h"
28 #include "get_bits.h"
29 #include "dnxhddata.h"
30 #include "dsputil.h"
31 #include "internal.h"
32 
33 typedef struct DNXHDContext {
36  int cid;
37  unsigned int width, height;
38  unsigned int mb_width, mb_height;
39  uint32_t mb_scan_index[68]; /* max for 1080p */
40  int cur_field;
42  int last_dc[3];
44  DECLARE_ALIGNED(16, int16_t, blocks)[12][64];
47  int bit_depth; // 8, 10 or 0 if not initialized at all.
48  int is_444;
49  void (*decode_dct_block)(struct DNXHDContext *ctx, int16_t *block,
50  int n, int qscale);
51 } DNXHDContext;
52 
53 #define DNXHD_VLC_BITS 9
54 #define DNXHD_DC_VLC_BITS 7
55 
56 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, int16_t *block, int n, int qscale);
57 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, int16_t *block, int n, int qscale);
58 static void dnxhd_decode_dct_block_10_444(DNXHDContext *ctx, int16_t *block, int n, int qscale);
59 
61 {
62  DNXHDContext *ctx = avctx->priv_data;
63 
64  ctx->avctx = avctx;
65  return 0;
66 }
67 
68 static int dnxhd_init_vlc(DNXHDContext *ctx, int cid)
69 {
70  if (cid != ctx->cid) {
71  int index;
72 
73  if ((index = ff_dnxhd_get_cid_table(cid)) < 0) {
74  av_log(ctx->avctx, AV_LOG_ERROR, "unsupported cid %d\n", cid);
75  return AVERROR(ENOSYS);
76  }
78 
79  ff_free_vlc(&ctx->ac_vlc);
80  ff_free_vlc(&ctx->dc_vlc);
81  ff_free_vlc(&ctx->run_vlc);
82 
83  init_vlc(&ctx->ac_vlc, DNXHD_VLC_BITS, 257,
84  ctx->cid_table->ac_bits, 1, 1,
85  ctx->cid_table->ac_codes, 2, 2, 0);
86  init_vlc(&ctx->dc_vlc, DNXHD_DC_VLC_BITS, ctx->bit_depth + 4,
87  ctx->cid_table->dc_bits, 1, 1,
88  ctx->cid_table->dc_codes, 1, 1, 0);
89  init_vlc(&ctx->run_vlc, DNXHD_VLC_BITS, 62,
90  ctx->cid_table->run_bits, 1, 1,
91  ctx->cid_table->run_codes, 2, 2, 0);
92 
94  ctx->cid = cid;
95  }
96  return 0;
97 }
98 
99 static int dnxhd_decode_header(DNXHDContext *ctx, AVFrame *frame,
100  const uint8_t *buf, int buf_size, int first_field)
101 {
102  static const uint8_t header_prefix[] = { 0x00, 0x00, 0x02, 0x80, 0x01 };
103  static const uint8_t header_prefix444[] = { 0x00, 0x00, 0x02, 0x80, 0x02 };
104  int i, cid, ret;
105 
106  if (buf_size < 0x280)
107  return AVERROR_INVALIDDATA;
108 
109  if (memcmp(buf, header_prefix, 5) && memcmp(buf, header_prefix444, 5)) {
110  av_log(ctx->avctx, AV_LOG_ERROR, "error in header\n");
111  return AVERROR_INVALIDDATA;
112  }
113  if (buf[5] & 2) { /* interlaced */
114  ctx->cur_field = buf[5] & 1;
115  frame->interlaced_frame = 1;
116  frame->top_field_first = first_field ^ ctx->cur_field;
117  av_log(ctx->avctx, AV_LOG_DEBUG, "interlaced %d, cur field %d\n", buf[5] & 3, ctx->cur_field);
118  }
119 
120  ctx->height = AV_RB16(buf + 0x18);
121  ctx->width = AV_RB16(buf + 0x1a);
122 
123  av_dlog(ctx->avctx, "width %d, height %d\n", ctx->width, ctx->height);
124 
125  ctx->is_444 = 0;
126  if (buf[0x4] == 0x2) {
128  ctx->avctx->bits_per_raw_sample = 10;
129  if (ctx->bit_depth != 10) {
130  ff_dsputil_init(&ctx->dsp, ctx->avctx);
131  ctx->bit_depth = 10;
133  }
134  ctx->is_444 = 1;
135  } else if (buf[0x21] & 0x40) {
137  ctx->avctx->bits_per_raw_sample = 10;
138  if (ctx->bit_depth != 10) {
139  ff_dsputil_init(&ctx->dsp, ctx->avctx);
140  ctx->bit_depth = 10;
142  }
143  } else {
145  ctx->avctx->bits_per_raw_sample = 8;
146  if (ctx->bit_depth != 8) {
147  ff_dsputil_init(&ctx->dsp, ctx->avctx);
148  ctx->bit_depth = 8;
150  }
151  }
152 
153  cid = AV_RB32(buf + 0x28);
154  av_dlog(ctx->avctx, "compression id %d\n", cid);
155 
156  if ((ret = dnxhd_init_vlc(ctx, cid)) < 0)
157  return ret;
158 
159  if (buf_size < ctx->cid_table->coding_unit_size) {
160  av_log(ctx->avctx, AV_LOG_ERROR, "incorrect frame size\n");
161  return AVERROR_INVALIDDATA;
162  }
163 
164  ctx->mb_width = ctx->width>>4;
165  ctx->mb_height = buf[0x16d];
166 
167  av_dlog(ctx->avctx, "mb width %d, mb height %d\n", ctx->mb_width, ctx->mb_height);
168 
169  if ((ctx->height+15)>>4 == ctx->mb_height && frame->interlaced_frame)
170  ctx->height <<= 1;
171 
172  if (ctx->mb_height > 68 ||
173  (ctx->mb_height << frame->interlaced_frame) > (ctx->height+15)>>4) {
174  av_log(ctx->avctx, AV_LOG_ERROR, "mb height too big: %d\n", ctx->mb_height);
175  return AVERROR_INVALIDDATA;
176  }
177 
178  for (i = 0; i < ctx->mb_height; i++) {
179  ctx->mb_scan_index[i] = AV_RB32(buf + 0x170 + (i<<2));
180  av_dlog(ctx->avctx, "mb scan index %d\n", ctx->mb_scan_index[i]);
181  if (buf_size < ctx->mb_scan_index[i] + 0x280) {
182  av_log(ctx->avctx, AV_LOG_ERROR, "invalid mb scan index\n");
183  return AVERROR_INVALIDDATA;
184  }
185  }
186 
187  return 0;
188 }
189 
191  int16_t *block, int n,
192  int qscale,
193  int index_bits,
194  int level_bias,
195  int level_shift)
196 {
197  int i, j, index1, index2, len;
198  int level, component, sign;
199  const uint8_t *weight_matrix;
200  OPEN_READER(bs, &ctx->gb);
201 
202  if (!ctx->is_444) {
203  if (n&2) {
204  component = 1 + (n&1);
205  weight_matrix = ctx->cid_table->chroma_weight;
206  } else {
207  component = 0;
208  weight_matrix = ctx->cid_table->luma_weight;
209  }
210  } else {
211  component = (n >> 1) % 3;
212  if (component) {
213  weight_matrix = ctx->cid_table->chroma_weight;
214  } else {
215  weight_matrix = ctx->cid_table->luma_weight;
216  }
217  }
218 
219  UPDATE_CACHE(bs, &ctx->gb);
220  GET_VLC(len, bs, &ctx->gb, ctx->dc_vlc.table, DNXHD_DC_VLC_BITS, 1);
221  if (len) {
222  level = GET_CACHE(bs, &ctx->gb);
223  LAST_SKIP_BITS(bs, &ctx->gb, len);
224  sign = ~level >> 31;
225  level = (NEG_USR32(sign ^ level, len) ^ sign) - sign;
226  ctx->last_dc[component] += level;
227  }
228  block[0] = ctx->last_dc[component];
229 
230  for (i = 1; ; i++) {
231  UPDATE_CACHE(bs, &ctx->gb);
232  GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
233  DNXHD_VLC_BITS, 2);
234  level = ctx->cid_table->ac_level[index1];
235  if (!level) /* EOB */
236  break;
237 
238  sign = SHOW_SBITS(bs, &ctx->gb, 1);
239  SKIP_BITS(bs, &ctx->gb, 1);
240 
241  if (ctx->cid_table->ac_index_flag[index1]) {
242  level += SHOW_UBITS(bs, &ctx->gb, index_bits) << 6;
243  SKIP_BITS(bs, &ctx->gb, index_bits);
244  }
245 
246  if (ctx->cid_table->ac_run_flag[index1]) {
247  UPDATE_CACHE(bs, &ctx->gb);
248  GET_VLC(index2, bs, &ctx->gb, ctx->run_vlc.table,
249  DNXHD_VLC_BITS, 2);
250  i += ctx->cid_table->run[index2];
251  }
252 
253  if (i > 63) {
254  av_log(ctx->avctx, AV_LOG_ERROR, "ac tex damaged %d, %d\n", n, i);
255  break;
256  }
257 
258  j = ctx->scantable.permutated[i];
259  level = (2*level+1) * qscale * weight_matrix[i];
260  if (level_bias < 32 || weight_matrix[i] != level_bias)
261  level += level_bias;
262  level >>= level_shift;
263 
264  block[j] = (level^sign) - sign;
265  }
266 
267  CLOSE_READER(bs, &ctx->gb);
268 }
269 
270 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, int16_t *block,
271  int n, int qscale)
272 {
273  dnxhd_decode_dct_block(ctx, block, n, qscale, 4, 32, 6);
274 }
275 
276 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, int16_t *block,
277  int n, int qscale)
278 {
279  dnxhd_decode_dct_block(ctx, block, n, qscale, 6, 8, 4);
280 }
281 
283  int n, int qscale)
284 {
285  dnxhd_decode_dct_block(ctx, block, n, qscale, 6, 32, 6);
286 }
287 
288 static int dnxhd_decode_macroblock(DNXHDContext *ctx, AVFrame *frame, int x, int y)
289 {
290  int shift1 = ctx->bit_depth == 10;
291  int dct_linesize_luma = frame->linesize[0];
292  int dct_linesize_chroma = frame->linesize[1];
293  uint8_t *dest_y, *dest_u, *dest_v;
294  int dct_y_offset, dct_x_offset;
295  int qscale, i;
296 
297  qscale = get_bits(&ctx->gb, 11);
298  skip_bits1(&ctx->gb);
299 
300  for (i = 0; i < 8; i++) {
301  ctx->dsp.clear_block(ctx->blocks[i]);
302  ctx->decode_dct_block(ctx, ctx->blocks[i], i, qscale);
303  }
304  if (ctx->is_444) {
305  for (; i < 12; i++) {
306  ctx->dsp.clear_block(ctx->blocks[i]);
307  ctx->decode_dct_block(ctx, ctx->blocks[i], i, qscale);
308  }
309  }
310 
311  if (frame->interlaced_frame) {
312  dct_linesize_luma <<= 1;
313  dct_linesize_chroma <<= 1;
314  }
315 
316  dest_y = frame->data[0] + ((y * dct_linesize_luma) << 4) + (x << (4 + shift1));
317  dest_u = frame->data[1] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1 + ctx->is_444));
318  dest_v = frame->data[2] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1 + ctx->is_444));
319 
320  if (ctx->cur_field) {
321  dest_y += frame->linesize[0];
322  dest_u += frame->linesize[1];
323  dest_v += frame->linesize[2];
324  }
325 
326  dct_y_offset = dct_linesize_luma << 3;
327  dct_x_offset = 8 << shift1;
328  if (!ctx->is_444) {
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  } else {
342  ctx->dsp.idct_put(dest_y, dct_linesize_luma, ctx->blocks[0]);
343  ctx->dsp.idct_put(dest_y + dct_x_offset, dct_linesize_luma, ctx->blocks[1]);
344  ctx->dsp.idct_put(dest_y + dct_y_offset, dct_linesize_luma, ctx->blocks[6]);
345  ctx->dsp.idct_put(dest_y + dct_y_offset + dct_x_offset, dct_linesize_luma, ctx->blocks[7]);
346 
347  if (!(ctx->avctx->flags & CODEC_FLAG_GRAY)) {
348  dct_y_offset = dct_linesize_chroma << 3;
349  ctx->dsp.idct_put(dest_u, dct_linesize_chroma, ctx->blocks[2]);
350  ctx->dsp.idct_put(dest_u + dct_x_offset, dct_linesize_chroma, ctx->blocks[3]);
351  ctx->dsp.idct_put(dest_u + dct_y_offset, dct_linesize_chroma, ctx->blocks[8]);
352  ctx->dsp.idct_put(dest_u + dct_y_offset + dct_x_offset, dct_linesize_chroma, ctx->blocks[9]);
353  ctx->dsp.idct_put(dest_v, dct_linesize_chroma, ctx->blocks[4]);
354  ctx->dsp.idct_put(dest_v + dct_x_offset, dct_linesize_chroma, ctx->blocks[5]);
355  ctx->dsp.idct_put(dest_v + dct_y_offset, dct_linesize_chroma, ctx->blocks[10]);
356  ctx->dsp.idct_put(dest_v + dct_y_offset + dct_x_offset, dct_linesize_chroma, ctx->blocks[11]);
357  }
358  }
359 
360  return 0;
361 }
362 
364  const uint8_t *buf, int buf_size)
365 {
366  int x, y;
367  for (y = 0; y < ctx->mb_height; y++) {
368  ctx->last_dc[0] =
369  ctx->last_dc[1] =
370  ctx->last_dc[2] = 1 << (ctx->bit_depth + 2); // for levels +2^(bitdepth-1)
371  init_get_bits(&ctx->gb, buf + ctx->mb_scan_index[y], (buf_size - ctx->mb_scan_index[y]) << 3);
372  for (x = 0; x < ctx->mb_width; x++) {
373  //START_TIMER;
374  dnxhd_decode_macroblock(ctx, frame, x, y);
375  //STOP_TIMER("decode macroblock");
376  }
377  }
378  return 0;
379 }
380 
381 static int dnxhd_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
382  AVPacket *avpkt)
383 {
384  const uint8_t *buf = avpkt->data;
385  int buf_size = avpkt->size;
386  DNXHDContext *ctx = avctx->priv_data;
387  AVFrame *picture = data;
388  int first_field = 1;
389  int ret;
390 
391  av_dlog(avctx, "frame size %d\n", buf_size);
392 
393  decode_coding_unit:
394  if ((ret = dnxhd_decode_header(ctx, picture, buf, buf_size, first_field)) < 0)
395  return ret;
396 
397  if ((avctx->width || avctx->height) &&
398  (ctx->width != avctx->width || ctx->height != avctx->height)) {
399  av_log(avctx, AV_LOG_WARNING, "frame size changed: %dx%d -> %dx%d\n",
400  avctx->width, avctx->height, ctx->width, ctx->height);
401  first_field = 1;
402  }
403 
404  ret = ff_set_dimensions(avctx, ctx->width, ctx->height);
405  if (ret < 0)
406  return ret;
407 
408  if (first_field) {
409  if ((ret = ff_get_buffer(avctx, picture, 0)) < 0) {
410  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
411  return ret;
412  }
413  picture->pict_type = AV_PICTURE_TYPE_I;
414  picture->key_frame = 1;
415  }
416 
417  dnxhd_decode_macroblocks(ctx, picture, buf + 0x280, buf_size - 0x280);
418 
419  if (first_field && picture->interlaced_frame) {
420  buf += ctx->cid_table->coding_unit_size;
421  buf_size -= ctx->cid_table->coding_unit_size;
422  first_field = 0;
423  goto decode_coding_unit;
424  }
425 
426  *got_frame = 1;
427  return buf_size;
428 }
429 
431 {
432  DNXHDContext *ctx = avctx->priv_data;
433 
434  ff_free_vlc(&ctx->ac_vlc);
435  ff_free_vlc(&ctx->dc_vlc);
436  ff_free_vlc(&ctx->run_vlc);
437  return 0;
438 }
439 
441  .name = "dnxhd",
442  .long_name = NULL_IF_CONFIG_SMALL("VC3/DNxHD"),
443  .type = AVMEDIA_TYPE_VIDEO,
444  .id = AV_CODEC_ID_DNXHD,
445  .priv_data_size = sizeof(DNXHDContext),
449  .capabilities = CODEC_CAP_DR1,
450 };