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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 #include "libavutil/imgutils.h"
26 #include "avcodec.h"
27 #include "get_bits.h"
28 #include "dnxhddata.h"
29 #include "dsputil.h"
30 #include "internal.h"
31 #include "thread.h"
32 
33 typedef struct DNXHDContext {
36  int64_t cid; ///< compression id
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; ///< current interlaced field
42  int last_dc[3];
44  DECLARE_ALIGNED(16, int16_t, blocks)[8][64];
47  int bit_depth; // 8, 10 or 0 if not initialized at all.
48  void (*decode_dct_block)(struct DNXHDContext *ctx, int16_t *block,
49  int n, int qscale);
51  int luma_scale[64];
52  int chroma_scale[64];
53 } DNXHDContext;
54 
55 #define DNXHD_VLC_BITS 9
56 #define DNXHD_DC_VLC_BITS 7
57 
58 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, int16_t *block, int n, int qscale);
59 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, int16_t *block, int n, int qscale);
60 
62 {
63  DNXHDContext *ctx = avctx->priv_data;
64 
65  ctx->avctx = avctx;
66  ctx->cid = -1;
67  return 0;
68 }
69 
70 static int dnxhd_init_vlc(DNXHDContext *ctx, uint32_t cid)
71 {
72  if (cid != ctx->cid) {
73  int index;
74 
75  if ((index = ff_dnxhd_get_cid_table(cid)) < 0) {
76  av_log(ctx->avctx, AV_LOG_ERROR, "unsupported cid %d\n", cid);
77  return -1;
78  }
79  if (ff_dnxhd_cid_table[index].bit_depth != ctx->bit_depth) {
80  av_log(ctx->avctx, AV_LOG_ERROR, "bit depth mismatches %d %d\n", ff_dnxhd_cid_table[index].bit_depth, ctx->bit_depth);
81  return AVERROR_INVALIDDATA;
82  }
84 
85  ff_free_vlc(&ctx->ac_vlc);
86  ff_free_vlc(&ctx->dc_vlc);
87  ff_free_vlc(&ctx->run_vlc);
88 
89  init_vlc(&ctx->ac_vlc, DNXHD_VLC_BITS, 257,
90  ctx->cid_table->ac_bits, 1, 1,
91  ctx->cid_table->ac_codes, 2, 2, 0);
92  init_vlc(&ctx->dc_vlc, DNXHD_DC_VLC_BITS, ctx->bit_depth + 4,
93  ctx->cid_table->dc_bits, 1, 1,
94  ctx->cid_table->dc_codes, 1, 1, 0);
95  init_vlc(&ctx->run_vlc, DNXHD_VLC_BITS, 62,
96  ctx->cid_table->run_bits, 1, 1,
97  ctx->cid_table->run_codes, 2, 2, 0);
98 
100  ctx->cid = cid;
101  }
102  return 0;
103 }
104 
106  const uint8_t *buf, int buf_size, int first_field)
107 {
108  static const uint8_t header_prefix[] = { 0x00, 0x00, 0x02, 0x80, 0x01 };
109  int i, cid;
110 
111  if (buf_size < 0x280)
112  return -1;
113 
114  if (memcmp(buf, header_prefix, 5)) {
115  av_log(ctx->avctx, AV_LOG_ERROR, "error in header\n");
116  return -1;
117  }
118  if (buf[5] & 2) { /* interlaced */
119  ctx->cur_field = buf[5] & 1;
120  frame->interlaced_frame = 1;
121  frame->top_field_first = first_field ^ ctx->cur_field;
122  av_log(ctx->avctx, AV_LOG_DEBUG, "interlaced %d, cur field %d\n", buf[5] & 3, ctx->cur_field);
123  }
124 
125  ctx->height = AV_RB16(buf + 0x18);
126  ctx->width = AV_RB16(buf + 0x1a);
127 
128  av_dlog(ctx->avctx, "width %d, height %d\n", ctx->width, ctx->height);
129 
130  if (buf[0x21] & 0x40) {
132  ctx->avctx->bits_per_raw_sample = 10;
133  if (ctx->bit_depth != 10) {
134  ff_dsputil_init(&ctx->dsp, ctx->avctx);
135  ctx->bit_depth = 10;
137  }
138  } else {
140  ctx->avctx->bits_per_raw_sample = 8;
141  if (ctx->bit_depth != 8) {
142  ff_dsputil_init(&ctx->dsp, ctx->avctx);
143  ctx->bit_depth = 8;
145  }
146  }
147 
148  cid = AV_RB32(buf + 0x28);
149  av_dlog(ctx->avctx, "compression id %d\n", cid);
150 
151  if (dnxhd_init_vlc(ctx, cid) < 0)
152  return -1;
153 
154  if (buf_size < ctx->cid_table->coding_unit_size) {
155  av_log(ctx->avctx, AV_LOG_ERROR, "incorrect frame size\n");
156  return -1;
157  }
158 
159  ctx->mb_width = ctx->width>>4;
160  ctx->mb_height = buf[0x16d];
161 
162  av_dlog(ctx->avctx, "mb width %d, mb height %d\n", ctx->mb_width, ctx->mb_height);
163 
164  if ((ctx->height+15)>>4 == ctx->mb_height && frame->interlaced_frame)
165  ctx->height <<= 1;
166 
167  if (ctx->mb_height > 68 ||
168  (ctx->mb_height << frame->interlaced_frame) > (ctx->height+15)>>4) {
169  av_log(ctx->avctx, AV_LOG_ERROR, "mb height too big: %d\n", ctx->mb_height);
170  return -1;
171  }
172 
173  for (i = 0; i < ctx->mb_height; i++) {
174  ctx->mb_scan_index[i] = AV_RB32(buf + 0x170 + (i<<2));
175  av_dlog(ctx->avctx, "mb scan index %d\n", ctx->mb_scan_index[i]);
176  if (buf_size < ctx->mb_scan_index[i] + 0x280LL) {
177  av_log(ctx->avctx, AV_LOG_ERROR, "invalid mb scan index\n");
178  return -1;
179  }
180  }
181 
182  return 0;
183 }
184 
186  int16_t *block, int n,
187  int qscale,
188  int index_bits,
189  int level_bias,
190  int level_shift)
191 {
192  int i, j, index1, index2, len, flags;
193  int level, component, sign;
194  const int *scale;
195  const uint8_t *weight_matrix;
196  const uint8_t *ac_level = ctx->cid_table->ac_level;
197  const uint8_t *ac_flags = ctx->cid_table->ac_flags;
198  const int eob_index = ctx->cid_table->eob_index;
199  OPEN_READER(bs, &ctx->gb);
200 
201  if (n&2) {
202  component = 1 + (n&1);
203  scale = ctx->chroma_scale;
204  weight_matrix = ctx->cid_table->chroma_weight;
205  } else {
206  component = 0;
207  scale = ctx->luma_scale;
208  weight_matrix = ctx->cid_table->luma_weight;
209  }
210 
211  UPDATE_CACHE(bs, &ctx->gb);
212  GET_VLC(len, bs, &ctx->gb, ctx->dc_vlc.table, DNXHD_DC_VLC_BITS, 1);
213  if (len) {
214  level = GET_CACHE(bs, &ctx->gb);
215  LAST_SKIP_BITS(bs, &ctx->gb, len);
216  sign = ~level >> 31;
217  level = (NEG_USR32(sign ^ level, len) ^ sign) - sign;
218  ctx->last_dc[component] += level;
219  }
220  block[0] = ctx->last_dc[component];
221 
222  i = 0;
223 
224  UPDATE_CACHE(bs, &ctx->gb);
225  GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
226  DNXHD_VLC_BITS, 2);
227 
228  while (index1 != eob_index) {
229  level = ac_level[index1];
230  flags = ac_flags[index1];
231 
232  sign = SHOW_SBITS(bs, &ctx->gb, 1);
233  SKIP_BITS(bs, &ctx->gb, 1);
234 
235  if (flags & 1) {
236  level += SHOW_UBITS(bs, &ctx->gb, index_bits) << 7;
237  SKIP_BITS(bs, &ctx->gb, index_bits);
238  }
239 
240  if (flags & 2) {
241  UPDATE_CACHE(bs, &ctx->gb);
242  GET_VLC(index2, bs, &ctx->gb, ctx->run_vlc.table,
243  DNXHD_VLC_BITS, 2);
244  i += ctx->cid_table->run[index2];
245  }
246 
247  if (++i > 63) {
248  av_log(ctx->avctx, AV_LOG_ERROR, "ac tex damaged %d, %d\n", n, i);
249  break;
250  }
251 
252  j = ctx->scantable.permutated[i];
253  level *= scale[i];
254  if (level_bias < 32 || weight_matrix[i] != level_bias)
255  level += level_bias;
256  level >>= level_shift;
257 
258  block[j] = (level^sign) - sign;
259 
260  UPDATE_CACHE(bs, &ctx->gb);
261  GET_VLC(index1, bs, &ctx->gb, ctx->ac_vlc.table,
262  DNXHD_VLC_BITS, 2);
263  }
264 
265  CLOSE_READER(bs, &ctx->gb);
266 }
267 
268 static void dnxhd_decode_dct_block_8(DNXHDContext *ctx, int16_t *block,
269  int n, int qscale)
270 {
271  dnxhd_decode_dct_block(ctx, block, n, qscale, 4, 32, 6);
272 }
273 
274 static void dnxhd_decode_dct_block_10(DNXHDContext *ctx, int16_t *block,
275  int n, int qscale)
276 {
277  dnxhd_decode_dct_block(ctx, block, n, qscale, 6, 8, 4);
278 }
279 
280 static int dnxhd_decode_macroblock(DNXHDContext *ctx, AVFrame *frame, int x, int y)
281 {
282  int shift1 = ctx->bit_depth == 10;
283  int dct_linesize_luma = frame->linesize[0];
284  int dct_linesize_chroma = frame->linesize[1];
285  uint8_t *dest_y, *dest_u, *dest_v;
286  int dct_y_offset, dct_x_offset;
287  int qscale, i;
288 
289  qscale = get_bits(&ctx->gb, 11);
290  skip_bits1(&ctx->gb);
291 
292  if (qscale != ctx->last_qscale) {
293  for (i = 0; i < 64; i++) {
294  ctx->luma_scale[i] = qscale * ctx->cid_table->luma_weight[i];
295  ctx->chroma_scale[i] = qscale * ctx->cid_table->chroma_weight[i];
296  }
297  ctx->last_qscale = qscale;
298  }
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 
305  if (frame->interlaced_frame) {
306  dct_linesize_luma <<= 1;
307  dct_linesize_chroma <<= 1;
308  }
309 
310  dest_y = frame->data[0] + ((y * dct_linesize_luma) << 4) + (x << (4 + shift1));
311  dest_u = frame->data[1] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1));
312  dest_v = frame->data[2] + ((y * dct_linesize_chroma) << 4) + (x << (3 + shift1));
313 
314  if (ctx->cur_field) {
315  dest_y += frame->linesize[0];
316  dest_u += frame->linesize[1];
317  dest_v += frame->linesize[2];
318  }
319 
320  dct_y_offset = dct_linesize_luma << 3;
321  dct_x_offset = 8 << shift1;
322  ctx->dsp.idct_put(dest_y, dct_linesize_luma, ctx->blocks[0]);
323  ctx->dsp.idct_put(dest_y + dct_x_offset, dct_linesize_luma, ctx->blocks[1]);
324  ctx->dsp.idct_put(dest_y + dct_y_offset, dct_linesize_luma, ctx->blocks[4]);
325  ctx->dsp.idct_put(dest_y + dct_y_offset + dct_x_offset, dct_linesize_luma, ctx->blocks[5]);
326 
327  if (!(ctx->avctx->flags & CODEC_FLAG_GRAY)) {
328  dct_y_offset = dct_linesize_chroma << 3;
329  ctx->dsp.idct_put(dest_u, dct_linesize_chroma, ctx->blocks[2]);
330  ctx->dsp.idct_put(dest_v, dct_linesize_chroma, ctx->blocks[3]);
331  ctx->dsp.idct_put(dest_u + dct_y_offset, dct_linesize_chroma, ctx->blocks[6]);
332  ctx->dsp.idct_put(dest_v + dct_y_offset, dct_linesize_chroma, ctx->blocks[7]);
333  }
334 
335  return 0;
336 }
337 
339  const uint8_t *buf, int buf_size)
340 {
341  int x, y;
342  for (y = 0; y < ctx->mb_height; y++) {
343  ctx->last_dc[0] =
344  ctx->last_dc[1] =
345  ctx->last_dc[2] = 1 << (ctx->bit_depth + 2); // for levels +2^(bitdepth-1)
346  init_get_bits(&ctx->gb, buf + ctx->mb_scan_index[y], (buf_size - ctx->mb_scan_index[y]) << 3);
347  for (x = 0; x < ctx->mb_width; x++) {
348  //START_TIMER;
349  dnxhd_decode_macroblock(ctx, frame, x, y);
350  //STOP_TIMER("decode macroblock");
351  }
352  }
353  return 0;
354 }
355 
356 static int dnxhd_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
357  AVPacket *avpkt)
358 {
359  const uint8_t *buf = avpkt->data;
360  int buf_size = avpkt->size;
361  DNXHDContext *ctx = avctx->priv_data;
362  ThreadFrame frame = { .f = data };
363  AVFrame *picture = data;
364  int first_field = 1;
365  int ret;
366 
367  av_dlog(avctx, "frame size %d\n", buf_size);
368 
369  decode_coding_unit:
370  if (dnxhd_decode_header(ctx, picture, buf, buf_size, first_field) < 0)
371  return -1;
372 
373  if ((avctx->width || avctx->height) &&
374  (ctx->width != avctx->width || ctx->height != avctx->height)) {
375  av_log(avctx, AV_LOG_WARNING, "frame size changed: %dx%d -> %dx%d\n",
376  avctx->width, avctx->height, ctx->width, ctx->height);
377  first_field = 1;
378  }
379 
380  if (av_image_check_size(ctx->width, ctx->height, 0, avctx))
381  return -1;
382  avcodec_set_dimensions(avctx, ctx->width, ctx->height);
383 
384  if (first_field) {
385  if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
386  return ret;
387  picture->pict_type = AV_PICTURE_TYPE_I;
388  picture->key_frame = 1;
389  }
390 
391  dnxhd_decode_macroblocks(ctx, picture, buf + 0x280, buf_size - 0x280);
392 
393  if (first_field && picture->interlaced_frame) {
394  buf += ctx->cid_table->coding_unit_size;
395  buf_size -= ctx->cid_table->coding_unit_size;
396  first_field = 0;
397  goto decode_coding_unit;
398  }
399 
400  *got_frame = 1;
401  return avpkt->size;
402 }
403 
405 {
406  DNXHDContext *ctx = avctx->priv_data;
407 
408  ff_free_vlc(&ctx->ac_vlc);
409  ff_free_vlc(&ctx->dc_vlc);
410  ff_free_vlc(&ctx->run_vlc);
411  return 0;
412 }
413 
415  .name = "dnxhd",
416  .type = AVMEDIA_TYPE_VIDEO,
417  .id = AV_CODEC_ID_DNXHD,
418  .priv_data_size = sizeof(DNXHDContext),
422  .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
423  .long_name = NULL_IF_CONFIG_SMALL("VC3/DNxHD"),
424 };