FFmpeg
flashsv2enc.c
Go to the documentation of this file.
1 /*
2  * Flash Screen Video Version 2 encoder
3  * Copyright (C) 2009 Joshua Warner
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * Flash Screen Video Version 2 encoder
25  * @author Joshua Warner
26  */
27 
28 /* Differences from version 1 stream:
29  * NOTE: Currently, the only player that supports version 2 streams is Adobe Flash Player itself.
30  * * Supports sending only a range of scanlines in a block,
31  * indicating a difference from the corresponding block in the last keyframe.
32  * * Supports initializing the zlib dictionary with data from the corresponding
33  * block in the last keyframe, to improve compression.
34  * * Supports a hybrid 15-bit rgb / 7-bit palette color space.
35  */
36 
37 /* TODO:
38  * Don't keep Block structures for both current frame and keyframe.
39  * Make better heuristics for deciding stream parameters (optimum_* functions). Currently these return constants.
40  * Figure out how to encode palette information in the stream, choose an optimum palette at each keyframe.
41  * Figure out how the zlibPrimeCompressCurrent flag works, implement support.
42  * Find other sample files (that weren't generated here), develop a decoder.
43  */
44 
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <zlib.h>
48 
49 #include "libavutil/imgutils.h"
50 #include "avcodec.h"
51 #include "internal.h"
52 #include "put_bits.h"
53 #include "bytestream.h"
54 
55 #define HAS_IFRAME_IMAGE 0x02
56 #define HAS_PALLET_INFO 0x01
57 
58 #define COLORSPACE_BGR 0x00
59 #define COLORSPACE_15_7 0x10
60 #define HAS_DIFF_BLOCKS 0x04
61 #define ZLIB_PRIME_COMPRESS_CURRENT 0x02
62 #define ZLIB_PRIME_COMPRESS_PREVIOUS 0x01
63 
64 // Disables experimental "smart" parameter-choosing code, as well as the statistics that it depends on.
65 // At the moment, the "smart" code is a great example of how the parameters *shouldn't* be chosen.
66 #define FLASHSV2_DUMB
67 
68 typedef struct Block {
71  int enc_size;
73  unsigned long data_size;
74 
79 } Block;
80 
81 typedef struct Palette {
82  unsigned colors[128];
83  uint8_t index[1 << 15];
84 } Palette;
85 
86 typedef struct FlashSV2Context {
93 
96 
101 
102  int use15_7, dist, comp;
103 
104  int rows, cols;
105 
107 
108  int image_width, image_height;
109  int block_width, block_height;
112  uint8_t palette_type; ///< 0=>default, 1=>custom - changed when palette regenerated.
114 #ifndef FLASHSV2_DUMB
115  double tot_blocks; ///< blocks encoded since last keyframe
116  double diff_blocks; ///< blocks that were different since last keyframe
117  double tot_lines; ///< total scanlines in image since last keyframe
118  double diff_lines; ///< scanlines that were different since last keyframe
119  double raw_size; ///< size of raw frames since last keyframe
120  double comp_size; ///< size of compressed data since last keyframe
121  double uncomp_size; ///< size of uncompressed data since last keyframe
122 
123  double total_bits; ///< total bits written to stream so far
124 #endif
126 
128 {
129  av_freep(&s->encbuffer);
130  av_freep(&s->keybuffer);
131  av_freep(&s->databuffer);
132  av_freep(&s->blockbuffer);
133  av_freep(&s->current_frame);
134  av_freep(&s->key_frame);
135 
136  av_freep(&s->frame_blocks);
137  av_freep(&s->key_blocks);
138 }
139 
140 static void init_blocks(FlashSV2Context * s, Block * blocks,
141  uint8_t * encbuf, uint8_t * databuf)
142 {
143  int row, col;
144  Block *b;
145  memset(blocks, 0, s->cols * s->rows * sizeof(*blocks));
146  for (col = 0; col < s->cols; col++) {
147  for (row = 0; row < s->rows; row++) {
148  b = blocks + (col + row * s->cols);
149  b->width = (col < s->cols - 1) ?
150  s->block_width :
151  s->image_width - col * s->block_width;
152 
153  b->height = (row < s->rows - 1) ?
154  s->block_height :
155  s->image_height - row * s->block_height;
156 
157  b->row = row;
158  b->col = col;
159  b->enc = encbuf;
160  b->data = databuf;
161  encbuf += b->width * b->height * 3;
162  databuf += !databuf ? 0 : b->width * b->height * 6;
163  }
164  }
165 }
166 
168 {
169 #ifndef FLASHSV2_DUMB
170  s->diff_blocks = 0.1;
171  s->tot_blocks = 1;
172  s->diff_lines = 0.1;
173  s->tot_lines = 1;
174  s->raw_size = s->comp_size = s->uncomp_size = 10;
175 #endif
176 }
177 
178 static int update_block_dimensions(FlashSV2Context *s, int block_width, int block_height)
179 {
180  s->block_width = block_width;
181  s->block_height = block_height;
182  s->rows = (s->image_height + s->block_height - 1) / s->block_height;
183  s->cols = (s->image_width + s->block_width - 1) / s->block_width;
184  if (s->rows * s->cols > s->blocks_size / sizeof(Block)) {
185  s->frame_blocks = av_realloc_array(s->frame_blocks, s->rows, s->cols * sizeof(Block));
186  s->key_blocks = av_realloc_array(s->key_blocks, s->cols, s->rows * sizeof(Block));
187  if (!s->frame_blocks || !s->key_blocks) {
188  av_log(s->avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
189  return AVERROR(ENOMEM);
190  }
191  s->blocks_size = s->rows * s->cols * sizeof(Block);
192  }
194  init_blocks(s, s->key_blocks, s->keybuffer, 0);
195 
196  av_fast_malloc(&s->blockbuffer, &s->blockbuffer_size, block_width * block_height * 6);
197  if (!s->blockbuffer) {
198  av_log(s->avctx, AV_LOG_ERROR, "Could not allocate block buffer.\n");
199  return AVERROR(ENOMEM);
200  }
201  return 0;
202 }
203 
204 
206 {
207  FlashSV2Context *s = avctx->priv_data;
208  int ret;
209 
210  s->avctx = avctx;
211 
212  s->comp = avctx->compression_level;
213  if (s->comp == -1)
214  s->comp = 9;
215  if (s->comp < 0 || s->comp > 9) {
216  av_log(avctx, AV_LOG_ERROR,
217  "Compression level should be 0-9, not %d\n", s->comp);
218  return AVERROR(EINVAL);
219  }
220 
221 
222  if ((avctx->width > 4095) || (avctx->height > 4095)) {
223  av_log(avctx, AV_LOG_ERROR,
224  "Input dimensions too large, input must be max 4095x4095 !\n");
225  return AVERROR(EINVAL);
226  }
227  if ((avctx->width < 16) || (avctx->height < 16)) {
228  av_log(avctx, AV_LOG_ERROR,
229  "Input dimensions too small, input must be at least 16x16 !\n");
230  return AVERROR(EINVAL);
231  }
232 
233  if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
234  return ret;
235 
236 
237  s->last_key_frame = 0;
238 
239  s->image_width = avctx->width;
240  s->image_height = avctx->height;
241 
242  s->frame_size = s->image_width * s->image_height * 3;
243 
246  s->databuffer = av_mallocz(s->frame_size * 6);
249  if (!s->encbuffer || !s->keybuffer || !s->databuffer
250  || !s->current_frame || !s->key_frame) {
251  av_log(avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
252  return AVERROR(ENOMEM);
253  }
254 
255  reset_stats(s);
256 #ifndef FLASHSV2_DUMB
257  s->total_bits = 1;
258 #endif
259 
260  s->use_custom_palette = 0;
261  s->palette_type = -1; // so that the palette will be generated in reconfigure_at_keyframe
262 
263  return update_block_dimensions(s, 64, 64);
264 }
265 
267 {
268  int i;
269  memcpy(s->key_blocks, s->frame_blocks, s->blocks_size);
270  memcpy(s->key_frame, s->current_frame, s->frame_size);
271 
272  for (i = 0; i < s->rows * s->cols; i++) {
273  s->key_blocks[i].enc += (s->keybuffer - s->encbuffer);
274  s->key_blocks[i].sl_begin = 0;
275  s->key_blocks[i].sl_end = 0;
276  s->key_blocks[i].data = 0;
277  }
278  memcpy(s->keybuffer, s->encbuffer, s->frame_size);
279 
280  return 0;
281 }
282 
283 static int write_palette(FlashSV2Context * s, uint8_t * buf, int buf_size)
284 {
285  //this isn't implemented yet! Default palette only!
286  return -1;
287 }
288 
289 static int write_header(FlashSV2Context * s, uint8_t * buf, int buf_size)
290 {
291  PutBitContext pb;
292  int buf_pos, len;
293 
294  if (buf_size < 5)
295  return -1;
296 
297  init_put_bits(&pb, buf, buf_size);
298 
299  put_bits(&pb, 4, (s->block_width >> 4) - 1);
300  put_bits(&pb, 12, s->image_width);
301  put_bits(&pb, 4, (s->block_height >> 4) - 1);
302  put_bits(&pb, 12, s->image_height);
303 
304  flush_put_bits(&pb);
305  buf_pos = 4;
306 
307  buf[buf_pos++] = s->flags;
308 
309  if (s->flags & HAS_PALLET_INFO) {
310  len = write_palette(s, buf + buf_pos, buf_size - buf_pos);
311  if (len < 0)
312  return -1;
313  buf_pos += len;
314  }
315 
316  return buf_pos;
317 }
318 
319 static int write_block(Block * b, uint8_t * buf, int buf_size)
320 {
321  int buf_pos = 0;
322  unsigned block_size = b->data_size;
323 
324  if (b->flags & HAS_DIFF_BLOCKS)
325  block_size += 2;
327  block_size += 2;
328  if (block_size > 0)
329  block_size += 1;
330  if (buf_size < block_size + 2)
331  return -1;
332 
333  buf[buf_pos++] = block_size >> 8;
334  buf[buf_pos++] = block_size;
335 
336  if (block_size == 0)
337  return buf_pos;
338 
339  buf[buf_pos++] = b->flags;
340 
341  if (b->flags & HAS_DIFF_BLOCKS) {
342  buf[buf_pos++] = (b->start);
343  buf[buf_pos++] = (b->len);
344  }
345 
347  //This feature of the format is poorly understood, and as of now, unused.
348  buf[buf_pos++] = (b->col);
349  buf[buf_pos++] = (b->row);
350  }
351 
352  memcpy(buf + buf_pos, b->data, b->data_size);
353 
354  buf_pos += b->data_size;
355 
356  return buf_pos;
357 }
358 
359 static int encode_zlib(Block * b, uint8_t * buf, unsigned long *buf_size, int comp)
360 {
361  int res = compress2(buf, buf_size, b->sl_begin, b->sl_end - b->sl_begin, comp);
362  return res == Z_OK ? 0 : -1;
363 }
364 
365 static int encode_zlibprime(Block * b, Block * prime, uint8_t * buf,
366  int *buf_size, int comp)
367 {
368  z_stream s;
369  int res;
370  s.zalloc = NULL;
371  s.zfree = NULL;
372  s.opaque = NULL;
373  res = deflateInit(&s, comp);
374  if (res < 0)
375  return -1;
376 
377  s.next_in = prime->enc;
378  s.avail_in = prime->enc_size;
379  while (s.avail_in > 0) {
380  s.next_out = buf;
381  s.avail_out = *buf_size;
382  res = deflate(&s, Z_SYNC_FLUSH);
383  if (res < 0)
384  return -1;
385  }
386 
387  s.next_in = b->sl_begin;
388  s.avail_in = b->sl_end - b->sl_begin;
389  s.next_out = buf;
390  s.avail_out = *buf_size;
391  res = deflate(&s, Z_FINISH);
392  deflateEnd(&s);
393  *buf_size -= s.avail_out;
394  if (res != Z_STREAM_END)
395  return -1;
396  return 0;
397 }
398 
399 static int encode_bgr(Block * b, const uint8_t * src, int stride)
400 {
401  int i;
402  uint8_t *ptr = b->enc;
403  for (i = 0; i < b->start; i++)
404  memcpy(ptr + i * b->width * 3, src + i * stride, b->width * 3);
405  b->sl_begin = ptr + i * b->width * 3;
406  for (; i < b->start + b->len; i++)
407  memcpy(ptr + i * b->width * 3, src + i * stride, b->width * 3);
408  b->sl_end = ptr + i * b->width * 3;
409  for (; i < b->height; i++)
410  memcpy(ptr + i * b->width * 3, src + i * stride, b->width * 3);
411  b->enc_size = ptr + i * b->width * 3 - b->enc;
412  return b->enc_size;
413 }
414 
415 static inline unsigned pixel_color15(const uint8_t * src)
416 {
417  return (src[0] >> 3) | ((src[1] & 0xf8) << 2) | ((src[2] & 0xf8) << 7);
418 }
419 
420 static inline unsigned int chroma_diff(unsigned int c1, unsigned int c2)
421 {
422 #define ABSDIFF(a,b) (abs((int)(a)-(int)(b)))
423 
424  unsigned int t1 = (c1 & 0x000000ff) + ((c1 & 0x0000ff00) >> 8) + ((c1 & 0x00ff0000) >> 16);
425  unsigned int t2 = (c2 & 0x000000ff) + ((c2 & 0x0000ff00) >> 8) + ((c2 & 0x00ff0000) >> 16);
426 
427  return ABSDIFF(t1, t2) + ABSDIFF(c1 & 0x000000ff, c2 & 0x000000ff) +
428  ABSDIFF((c1 & 0x0000ff00) >> 8 , (c2 & 0x0000ff00) >> 8) +
429  ABSDIFF((c1 & 0x00ff0000) >> 16, (c2 & 0x00ff0000) >> 16);
430 }
431 
432 static inline int pixel_color7_fast(Palette * palette, unsigned c15)
433 {
434  return palette->index[c15];
435 }
436 
437 static int pixel_color7_slow(Palette * palette, unsigned color)
438 {
439  int i, min = 0x7fffffff;
440  int minc = -1;
441  for (i = 0; i < 128; i++) {
442  int c1 = palette->colors[i];
443  int diff = chroma_diff(c1, color);
444  if (diff < min) {
445  min = diff;
446  minc = i;
447  }
448  }
449  return minc;
450 }
451 
452 static inline unsigned pixel_bgr(const uint8_t * src)
453 {
454  return (src[0]) | (src[1] << 8) | (src[2] << 16);
455 }
456 
457 static int write_pixel_15_7(Palette * palette, uint8_t * dest, const uint8_t * src,
458  int dist)
459 {
460  unsigned c15 = pixel_color15(src);
461  unsigned color = pixel_bgr(src);
462  int d15 = chroma_diff(color, color & 0x00f8f8f8);
463  int c7 = pixel_color7_fast(palette, c15);
464  int d7 = chroma_diff(color, palette->colors[c7]);
465  if (dist + d15 >= d7) {
466  dest[0] = c7;
467  return 1;
468  } else {
469  dest[0] = 0x80 | (c15 >> 8);
470  dest[1] = c15 & 0xff;
471  return 2;
472  }
473 }
474 
475 static int update_palette_index(Palette * palette)
476 {
477  int r, g, b;
478  unsigned int bgr, c15, index;
479  for (r = 4; r < 256; r += 8) {
480  for (g = 4; g < 256; g += 8) {
481  for (b = 4; b < 256; b += 8) {
482  bgr = b | (g << 8) | (r << 16);
483  c15 = (b >> 3) | ((g & 0xf8) << 2) | ((r & 0xf8) << 7);
484  index = pixel_color7_slow(palette, bgr);
485 
486  palette->index[c15] = index;
487  }
488  }
489  }
490  return 0;
491 }
492 
493 static const unsigned int default_screen_video_v2_palette[128] = {
494  0x00000000, 0x00333333, 0x00666666, 0x00999999, 0x00CCCCCC, 0x00FFFFFF,
495  0x00330000, 0x00660000, 0x00990000, 0x00CC0000, 0x00FF0000, 0x00003300,
496  0x00006600, 0x00009900, 0x0000CC00, 0x0000FF00, 0x00000033, 0x00000066,
497  0x00000099, 0x000000CC, 0x000000FF, 0x00333300, 0x00666600, 0x00999900,
498  0x00CCCC00, 0x00FFFF00, 0x00003333, 0x00006666, 0x00009999, 0x0000CCCC,
499  0x0000FFFF, 0x00330033, 0x00660066, 0x00990099, 0x00CC00CC, 0x00FF00FF,
500  0x00FFFF33, 0x00FFFF66, 0x00FFFF99, 0x00FFFFCC, 0x00FF33FF, 0x00FF66FF,
501  0x00FF99FF, 0x00FFCCFF, 0x0033FFFF, 0x0066FFFF, 0x0099FFFF, 0x00CCFFFF,
502  0x00CCCC33, 0x00CCCC66, 0x00CCCC99, 0x00CCCCFF, 0x00CC33CC, 0x00CC66CC,
503  0x00CC99CC, 0x00CCFFCC, 0x0033CCCC, 0x0066CCCC, 0x0099CCCC, 0x00FFCCCC,
504  0x00999933, 0x00999966, 0x009999CC, 0x009999FF, 0x00993399, 0x00996699,
505  0x0099CC99, 0x0099FF99, 0x00339999, 0x00669999, 0x00CC9999, 0x00FF9999,
506  0x00666633, 0x00666699, 0x006666CC, 0x006666FF, 0x00663366, 0x00669966,
507  0x0066CC66, 0x0066FF66, 0x00336666, 0x00996666, 0x00CC6666, 0x00FF6666,
508  0x00333366, 0x00333399, 0x003333CC, 0x003333FF, 0x00336633, 0x00339933,
509  0x0033CC33, 0x0033FF33, 0x00663333, 0x00993333, 0x00CC3333, 0x00FF3333,
510  0x00003366, 0x00336600, 0x00660033, 0x00006633, 0x00330066, 0x00663300,
511  0x00336699, 0x00669933, 0x00993366, 0x00339966, 0x00663399, 0x00996633,
512  0x006699CC, 0x0099CC66, 0x00CC6699, 0x0066CC99, 0x009966CC, 0x00CC9966,
513  0x0099CCFF, 0x00CCFF99, 0x00FF99CC, 0x0099FFCC, 0x00CC99FF, 0x00FFCC99,
514  0x00111111, 0x00222222, 0x00444444, 0x00555555, 0x00AAAAAA, 0x00BBBBBB,
515  0x00DDDDDD, 0x00EEEEEE
516 };
517 
518 static int generate_default_palette(Palette * palette)
519 {
520  memcpy(palette->colors, default_screen_video_v2_palette,
522 
523  return update_palette_index(palette);
524 }
525 
526 static int generate_optimum_palette(Palette * palette, const uint8_t * image,
527  int width, int height, int stride)
528 {
529  //this isn't implemented yet! Default palette only!
530  return -1;
531 }
532 
533 static inline int encode_15_7_sl(Palette * palette, uint8_t * dest,
534  const uint8_t * src, int width, int dist)
535 {
536  int len = 0, x;
537  for (x = 0; x < width; x++) {
538  len += write_pixel_15_7(palette, dest + len, src + 3 * x, dist);
539  }
540  return len;
541 }
542 
543 static int encode_15_7(Palette * palette, Block * b, const uint8_t * src,
544  int stride, int dist)
545 {
546  int i;
547  uint8_t *ptr = b->enc;
548  for (i = 0; i < b->start; i++)
549  ptr += encode_15_7_sl(palette, ptr, src + i * stride, b->width, dist);
550  b->sl_begin = ptr;
551  for (; i < b->start + b->len; i++)
552  ptr += encode_15_7_sl(palette, ptr, src + i * stride, b->width, dist);
553  b->sl_end = ptr;
554  for (; i < b->height; i++)
555  ptr += encode_15_7_sl(palette, ptr, src + i * stride, b->width, dist);
556  b->enc_size = ptr - b->enc;
557  return b->enc_size;
558 }
559 
560 static int encode_block(FlashSV2Context *s, Palette * palette, Block * b,
561  Block * prev, const uint8_t * src, int stride, int comp,
562  int dist, int keyframe)
563 {
564  unsigned buf_size = b->width * b->height * 6;
565  uint8_t *buf = s->blockbuffer;
566  int res;
567 
568  if (b->flags & COLORSPACE_15_7) {
569  encode_15_7(palette, b, src, stride, dist);
570  } else {
571  encode_bgr(b, src, stride);
572  }
573 
574  if (b->len > 0) {
575  b->data_size = buf_size;
576  res = encode_zlib(b, b->data, &b->data_size, comp);
577  if (res)
578  return res;
579 
580  if (!keyframe) {
581  res = encode_zlibprime(b, prev, buf, &buf_size, comp);
582  if (res)
583  return res;
584 
585  if (buf_size < b->data_size) {
586  b->data_size = buf_size;
587  memcpy(b->data, buf, buf_size);
589  }
590  }
591  } else {
592  b->data_size = 0;
593  }
594  return 0;
595 }
596 
597 static int compare_sl(FlashSV2Context * s, Block * b, const uint8_t * src,
598  uint8_t * frame, uint8_t * key, int y, int keyframe)
599 {
600  if (memcmp(src, frame, b->width * 3) != 0) {
601  b->dirty = 1;
602  memcpy(frame, src, b->width * 3);
603 #ifndef FLASHSV2_DUMB
604  s->diff_lines++;
605 #endif
606  }
607  if (memcmp(src, key, b->width * 3) != 0) {
608  if (b->len == 0)
609  b->start = y;
610  b->len = y + 1 - b->start;
611  }
612  return 0;
613 }
614 
615 static int mark_all_blocks(FlashSV2Context * s, const uint8_t * src, int stride,
616  int keyframe)
617 {
618  int sl, rsl, col, pos, possl;
619  Block *b;
620  for (sl = s->image_height - 1; sl >= 0; sl--) {
621  for (col = 0; col < s->cols; col++) {
622  rsl = s->image_height - sl - 1;
623  b = s->frame_blocks + col + rsl / s->block_height * s->cols;
624  possl = stride * sl + col * s->block_width * 3;
625  pos = s->image_width * rsl * 3 + col * s->block_width * 3;
626  compare_sl(s, b, src + possl, s->current_frame + pos,
627  s->key_frame + pos, rsl % s->block_height, keyframe);
628  }
629  }
630 #ifndef FLASHSV2_DUMB
631  s->tot_lines += s->image_height * s->cols;
632 #endif
633  return 0;
634 }
635 
636 static int encode_all_blocks(FlashSV2Context * s, int keyframe)
637 {
638  int row, col, res;
639  uint8_t *data;
640  Block *b, *prev;
641  for (row = 0; row < s->rows; row++) {
642  for (col = 0; col < s->cols; col++) {
643  b = s->frame_blocks + (row * s->cols + col);
644  prev = s->key_blocks + (row * s->cols + col);
645  b->flags = s->use15_7 ? COLORSPACE_15_7 : 0;
646  if (keyframe) {
647  b->start = 0;
648  b->len = b->height;
649  } else if (!b->dirty) {
650  b->start = 0;
651  b->len = 0;
652  b->data_size = 0;
653  continue;
654  } else if (b->start != 0 || b->len != b->height) {
655  b->flags |= HAS_DIFF_BLOCKS;
656  }
657  data = s->current_frame + s->image_width * 3 * s->block_height * row + s->block_width * col * 3;
658  res = encode_block(s, &s->palette, b, prev, data, s->image_width * 3, s->comp, s->dist, keyframe);
659 #ifndef FLASHSV2_DUMB
660  if (b->dirty)
661  s->diff_blocks++;
662  s->comp_size += b->data_size;
663  s->uncomp_size += b->enc_size;
664 #endif
665  if (res)
666  return res;
667  }
668  }
669 #ifndef FLASHSV2_DUMB
670  s->raw_size += s->image_width * s->image_height * 3;
671  s->tot_blocks += s->rows * s->cols;
672 #endif
673  return 0;
674 }
675 
677  int buf_size)
678 {
679  int row, col, buf_pos = 0, len;
680  Block *b;
681  for (row = 0; row < s->rows; row++) {
682  for (col = 0; col < s->cols; col++) {
683  b = s->frame_blocks + row * s->cols + col;
684  len = write_block(b, buf + buf_pos, buf_size - buf_pos);
685  b->start = b->len = b->dirty = 0;
686  if (len < 0)
687  return len;
688  buf_pos += len;
689  }
690  }
691  return buf_pos;
692 }
693 
694 static int write_bitstream(FlashSV2Context * s, const uint8_t * src, int stride,
695  uint8_t * buf, int buf_size, int keyframe)
696 {
697  int buf_pos, res;
698 
699  res = mark_all_blocks(s, src, stride, keyframe);
700  if (res)
701  return res;
702  res = encode_all_blocks(s, keyframe);
703  if (res)
704  return res;
705 
706  res = write_header(s, buf, buf_size);
707  if (res < 0) {
708  return res;
709  } else {
710  buf_pos = res;
711  }
712  res = write_all_blocks(s, buf + buf_pos, buf_size - buf_pos);
713  if (res < 0)
714  return res;
715  buf_pos += res;
716 #ifndef FLASHSV2_DUMB
717  s->total_bits += ((double) buf_pos) * 8.0;
718 #endif
719 
720  return buf_pos;
721 }
722 
723 static void recommend_keyframe(FlashSV2Context * s, int *keyframe)
724 {
725 #ifndef FLASHSV2_DUMB
726  double block_ratio, line_ratio, enc_ratio, comp_ratio, data_ratio;
727  if (s->avctx->gop_size > 0) {
728  block_ratio = s->diff_blocks / s->tot_blocks;
729  line_ratio = s->diff_lines / s->tot_lines;
730  enc_ratio = s->uncomp_size / s->raw_size;
731  comp_ratio = s->comp_size / s->uncomp_size;
732  data_ratio = s->comp_size / s->raw_size;
733 
734  if ((block_ratio >= 0.5 && line_ratio / block_ratio <= 0.5) || line_ratio >= 0.95) {
735  *keyframe = 1;
736  return;
737  }
738  }
739 #else
740  return;
741 #endif
742 }
743 
744 #ifndef FLASHSV2_DUMB
745 static const double block_size_fraction = 1.0 / 300;
746 static const double use15_7_threshold = 8192;
747 static const double color15_7_factor = 100;
748 #endif
750 {
751 #ifndef FLASHSV2_DUMB
752  double save = (1-pow(s->diff_lines/s->diff_blocks/s->block_height, 0.5)) * s->comp_size/s->tot_blocks;
753  double width = block_size_fraction * sqrt(0.5 * save * s->rows * s->cols) * s->image_width;
754  int pwidth = ((int) width);
755  return FFCLIP(pwidth & ~15, 256, 16);
756 #else
757  return 64;
758 #endif
759 }
760 
762 {
763 #ifndef FLASHSV2_DUMB
764  double save = (1-pow(s->diff_lines/s->diff_blocks/s->block_height, 0.5)) * s->comp_size/s->tot_blocks;
765  double height = block_size_fraction * sqrt(0.5 * save * s->rows * s->cols) * s->image_height;
766  int pheight = ((int) height);
767  return FFCLIP(pheight & ~15, 256, 16);
768 #else
769  return 64;
770 #endif
771 }
772 
774 {
775 #ifndef FLASHSV2_DUMB
776  double ideal = ((double)(s->avctx->bit_rate * s->avctx->time_base.den * s->avctx->ticks_per_frame)) /
777  ((double) s->avctx->time_base.num) * s->avctx->frame_number;
778  if (ideal + use15_7_threshold < s->total_bits) {
779  return 1;
780  } else {
781  return 0;
782  }
783 #else
784  return s->avctx->global_quality == 0;
785 #endif
786 }
787 
789 {
790 #ifndef FLASHSV2_DUMB
791  double ideal =
792  s->avctx->bit_rate * s->avctx->time_base.den *
794  int dist = pow((s->total_bits / ideal) * color15_7_factor, 3);
795  av_log(s->avctx, AV_LOG_DEBUG, "dist: %d\n", dist);
796  return dist;
797 #else
798  return 15;
799 #endif
800 }
801 
802 
803 static int reconfigure_at_keyframe(FlashSV2Context * s, const uint8_t * image,
804  int stride)
805 {
806  int update_palette = 0;
807  int res;
808  int block_width = optimum_block_width (s);
809  int block_height = optimum_block_height(s);
810 
811  if (block_width != s->block_width || block_height != s->block_height) {
812  res = update_block_dimensions(s, block_width, block_height);
813  if (res < 0)
814  return res;
815  }
816 
817  s->use15_7 = optimum_use15_7(s);
818  if (s->use15_7) {
819  if ((s->use_custom_palette && s->palette_type != 1) || update_palette) {
820  res = generate_optimum_palette(&s->palette, image, s->image_width, s->image_height, stride);
821  if (res)
822  return res;
823  s->palette_type = 1;
824  av_log(s->avctx, AV_LOG_DEBUG, "Generated optimum palette\n");
825  } else if (!s->use_custom_palette && s->palette_type != 0) {
827  if (res)
828  return res;
829  s->palette_type = 0;
830  av_log(s->avctx, AV_LOG_DEBUG, "Generated default palette\n");
831  }
832  }
833 
834 
835  reset_stats(s);
836 
837  return 0;
838 }
839 
841  const AVFrame *p, int *got_packet)
842 {
843  FlashSV2Context *const s = avctx->priv_data;
844  int res;
845  int keyframe = 0;
846 
847  if ((res = ff_alloc_packet2(avctx, pkt, s->frame_size + AV_INPUT_BUFFER_MIN_SIZE, 0)) < 0)
848  return res;
849 
850  /* First frame needs to be a keyframe */
851  if (avctx->frame_number == 0)
852  keyframe = 1;
853 
854  /* Check the placement of keyframes */
855  if (avctx->gop_size > 0) {
856  if (avctx->frame_number >= s->last_key_frame + avctx->gop_size)
857  keyframe = 1;
858  }
859 
860  if (!keyframe
861  && avctx->frame_number > s->last_key_frame + avctx->keyint_min) {
862  recommend_keyframe(s, &keyframe);
863  if (keyframe)
864  av_log(avctx, AV_LOG_DEBUG, "Recommending key frame at frame %d\n", avctx->frame_number);
865  }
866 
867  if (keyframe) {
868  res = reconfigure_at_keyframe(s, p->data[0], p->linesize[0]);
869  if (res)
870  return res;
871  }
872 
873  if (s->use15_7)
874  s->dist = optimum_dist(s);
875 
876  res = write_bitstream(s, p->data[0], p->linesize[0], pkt->data, pkt->size, keyframe);
877 
878  if (keyframe) {
879  new_key_frame(s);
880  s->last_key_frame = avctx->frame_number;
881  pkt->flags |= AV_PKT_FLAG_KEY;
882  av_log(avctx, AV_LOG_DEBUG, "Inserting key frame at frame %d\n", avctx->frame_number);
883  }
884 
885  pkt->size = res;
886  *got_packet = 1;
887 
888  return 0;
889 }
890 
892 {
893  FlashSV2Context *s = avctx->priv_data;
894 
895  cleanup(s);
896 
897  return 0;
898 }
899 
901  .name = "flashsv2",
902  .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video Version 2"),
903  .type = AVMEDIA_TYPE_VIDEO,
904  .id = AV_CODEC_ID_FLASHSV2,
905  .priv_data_size = sizeof(FlashSV2Context),
907  .encode2 = flashsv2_encode_frame,
908  .close = flashsv2_encode_end,
910  .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
911 };
#define FF_CODEC_CAP_INIT_CLEANUP
The codec allows calling the close function for deallocation even if the init function returned a fai...
Definition: internal.h:49
uint8_t use_custom_palette
Definition: flashsv2enc.c:111
uint8_t index[1<< 15]
Definition: flashsv2enc.c:83
#define NULL
Definition: coverity.c:32
static int compare_sl(FlashSV2Context *s, Block *b, const uint8_t *src, uint8_t *frame, uint8_t *key, int y, int keyframe)
Definition: flashsv2enc.c:597
static int optimum_block_width(FlashSV2Context *s)
Definition: flashsv2enc.c:749
static void recommend_keyframe(FlashSV2Context *s, int *keyframe)
Definition: flashsv2enc.c:723
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
static int new_key_frame(FlashSV2Context *s)
Definition: flashsv2enc.c:266
uint8_t len
Definition: flashsv2enc.c:75
static unsigned pixel_color15(const uint8_t *src)
Definition: flashsv2enc.c:415
Block * frame_blocks
Definition: flashsv2enc.c:97
static int optimum_use15_7(FlashSV2Context *s)
Definition: flashsv2enc.c:773
misc image utilities
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:218
int64_t bit_rate
the average bitrate
Definition: avcodec.h:581
static int encode_zlibprime(Block *b, Block *prime, uint8_t *buf, int *buf_size, int comp)
Definition: flashsv2enc.c:365
const char * g
Definition: vf_curves.c:117
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
int num
Numerator.
Definition: rational.h:59
static const unsigned int default_screen_video_v2_palette[128]
Definition: flashsv2enc.c:493
int size
Definition: packet.h:364
uint8_t * sl_begin
Definition: flashsv2enc.c:70
static int generate_optimum_palette(Palette *palette, const uint8_t *image, int width, int height, int stride)
Definition: flashsv2enc.c:526
uint8_t width
Definition: flashsv2enc.c:77
int enc_size
Definition: flashsv2enc.c:71
static int optimum_dist(FlashSV2Context *s)
Definition: flashsv2enc.c:788
const char * key
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:237
static AVPacket pkt
static int update_block_dimensions(FlashSV2Context *s, int block_width, int block_height)
Definition: flashsv2enc.c:178
AVCodec.
Definition: codec.h:190
AVCodecContext * avctx
Definition: flashsv2enc.c:87
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:654
static av_cold int flashsv2_encode_end(AVCodecContext *avctx)
Definition: flashsv2enc.c:891
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:33
#define HAS_PALLET_INFO
Definition: flashsv2enc.c:56
uint8_t
#define av_cold
Definition: attributes.h:88
static int generate_default_palette(Palette *palette)
Definition: flashsv2enc.c:518
static int flashsv2_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *p, int *got_packet)
Definition: flashsv2enc.c:840
uint8_t * data
Definition: flashsv2enc.c:72
static int encode_block(FlashSV2Context *s, Palette *palette, Block *b, Block *prev, const uint8_t *src, int stride, int comp, int dist, int keyframe)
Definition: flashsv2enc.c:560
#define ZLIB_PRIME_COMPRESS_CURRENT
Definition: flashsv2enc.c:61
uint8_t * data
Definition: packet.h:363
static const uint64_t c1
Definition: murmur3.c:51
uint8_t flags
Definition: flashsv2enc.c:78
#define COLORSPACE_15_7
Definition: flashsv2enc.c:59
static unsigned int chroma_diff(unsigned int c1, unsigned int c2)
Definition: flashsv2enc.c:420
Block * key_blocks
Definition: flashsv2enc.c:98
void * av_realloc_array(void *ptr, size_t nmemb, size_t size)
Definition: mem.c:198
#define AV_INPUT_BUFFER_MIN_SIZE
minimum encoding buffer size Used to avoid some checks during header writing.
Definition: avcodec.h:222
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:401
static av_cold int flashsv2_encode_init(AVCodecContext *avctx)
Definition: flashsv2enc.c:205
#define src
Definition: vp8dsp.c:255
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
#define ZLIB_PRIME_COMPRESS_PREVIOUS
Definition: flashsv2enc.c:62
static int encode_zlib(Block *b, uint8_t *buf, unsigned long *buf_size, int comp)
Definition: flashsv2enc.c:359
static int encode_15_7(Palette *palette, Block *b, const uint8_t *src, int stride, int dist)
Definition: flashsv2enc.c:543
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:115
uint8_t * blockbuffer
Definition: flashsv2enc.c:94
const char * r
Definition: vf_curves.c:116
unsigned int pos
Definition: spdifenc.c:412
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:215
#define t1
Definition: regdef.h:29
const char * name
Name of the codec implementation.
Definition: codec.h:197
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:369
AVCodec ff_flashsv2_encoder
Definition: flashsv2enc.c:900
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:502
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:317
#define b
Definition: input.c:41
uint8_t * databuffer
Definition: flashsv2enc.c:92
uint8_t dirty
Definition: flashsv2enc.c:76
int width
picture width / height.
Definition: avcodec.h:704
static int pixel_color7_slow(Palette *palette, unsigned color)
Definition: flashsv2enc.c:437
uint8_t * keybuffer
Definition: flashsv2enc.c:91
uint8_t * key_frame
Definition: flashsv2enc.c:89
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
static int write_block(Block *b, uint8_t *buf, int buf_size)
Definition: flashsv2enc.c:319
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
int ticks_per_frame
For some codecs, the time base is closer to the field rate than the frame rate.
Definition: avcodec.h:663
static int encode_bgr(Block *b, const uint8_t *src, int stride)
Definition: flashsv2enc.c:399
static int reconfigure_at_keyframe(FlashSV2Context *s, const uint8_t *image, int stride)
Definition: flashsv2enc.c:803
if(ret)
static void comp(unsigned char *dst, ptrdiff_t dst_stride, unsigned char *src, ptrdiff_t src_stride, int add)
Definition: eamad.c:85
#define HAS_DIFF_BLOCKS
Definition: flashsv2enc.c:60
static int write_palette(FlashSV2Context *s, uint8_t *buf, int buf_size)
Definition: flashsv2enc.c:283
static int update_palette_index(Palette *palette)
Definition: flashsv2enc.c:475
Libavcodec external API header.
int compression_level
Definition: avcodec.h:603
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:345
main external API structure.
Definition: avcodec.h:531
static int write_header(FlashSV2Context *s, uint8_t *buf, int buf_size)
Definition: flashsv2enc.c:289
unsigned long data_size
Definition: flashsv2enc.c:73
static int encode_15_7_sl(Palette *palette, uint8_t *dest, const uint8_t *src, int width, int dist)
Definition: flashsv2enc.c:533
uint8_t row
Definition: flashsv2enc.c:77
uint8_t start
Definition: flashsv2enc.c:75
static int mark_all_blocks(FlashSV2Context *s, const uint8_t *src, int stride, int keyframe)
Definition: flashsv2enc.c:615
int index
Definition: gxfenc.c:89
static int pixel_color7_fast(Palette *palette, unsigned c15)
Definition: flashsv2enc.c:432
static void init_blocks(FlashSV2Context *s, Block *blocks, uint8_t *encbuf, uint8_t *databuf)
Definition: flashsv2enc.c:140
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:303
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:597
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:328
uint8_t * enc
Definition: flashsv2enc.c:69
int gop_size
the number of pictures in a group of pictures, or 0 for intra_only
Definition: avcodec.h:726
uint8_t height
Definition: flashsv2enc.c:77
int
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:104
static unsigned pixel_bgr(const uint8_t *src)
Definition: flashsv2enc.c:452
uint8_t palette_type
0=>default, 1=>custom - changed when palette regenerated.
Definition: flashsv2enc.c:112
common internal api header.
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:117
static int write_all_blocks(FlashSV2Context *s, uint8_t *buf, int buf_size)
Definition: flashsv2enc.c:676
static const uint64_t c2
Definition: murmur3.c:52
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:64
int den
Denominator.
Definition: rational.h:60
unsigned colors[128]
Definition: flashsv2enc.c:82
static void deflate(uint8_t *dst, const uint8_t *p1, int width, int threshold, const uint8_t *coordinates[], int coord, int maxc)
Definition: vf_neighbor.c:165
void * priv_data
Definition: avcodec.h:558
static av_always_inline int diff(const uint32_t a, const uint32_t b)
uint8_t * current_frame
Definition: flashsv2enc.c:88
static int encode_all_blocks(FlashSV2Context *s, int keyframe)
Definition: flashsv2enc.c:636
int frame_number
Frame counter, set by libavcodec.
Definition: avcodec.h:1222
#define av_freep(p)
static int optimum_block_height(FlashSV2Context *s)
Definition: flashsv2enc.c:761
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
float min
#define ABSDIFF(a, b)
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: packet.h:340
static int write_bitstream(FlashSV2Context *s, const uint8_t *src, int stride, uint8_t *buf, int buf_size, int keyframe)
Definition: flashsv2enc.c:694
static int write_pixel_15_7(Palette *palette, uint8_t *dest, const uint8_t *src, int dist)
Definition: flashsv2enc.c:457
#define t2
Definition: regdef.h:30
int i
Definition: input.c:407
static void reset_stats(FlashSV2Context *s)
Definition: flashsv2enc.c:167
static av_cold void cleanup(FlashSV2Context *s)
Definition: flashsv2enc.c:127
uint8_t col
Definition: flashsv2enc.c:77
uint8_t * encbuffer
Definition: flashsv2enc.c:90
int keyint_min
minimum GOP size
Definition: avcodec.h:1112
uint8_t * sl_end
Definition: flashsv2enc.c:70
bitstream writer API