2 * Flash Screen Video Version 2 encoder
3 * Copyright (C) 2009 Joshua Warner
5 * This file is part of FFmpeg.
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.
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.
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
24 * Flash Screen Video Version 2 encoder
25 * @author Joshua Warner
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.
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.
49 #include "libavutil/imgutils.h"
51 #include "codec_internal.h"
54 #include "bytestream.h"
55 #include "zlib_wrapper.h"
57 #define HAS_IFRAME_IMAGE 0x02
58 #define HAS_PALLET_INFO 0x01
60 #define COLORSPACE_BGR 0x00
61 #define COLORSPACE_15_7 0x10
62 #define HAS_DIFF_BLOCKS 0x04
63 #define ZLIB_PRIME_COMPRESS_CURRENT 0x02
64 #define ZLIB_PRIME_COMPRESS_PREVIOUS 0x01
66 // Disables experimental "smart" parameter-choosing code, as well as the statistics that it depends on.
67 // At the moment, the "smart" code is a great example of how the parameters *shouldn't* be chosen.
70 typedef struct Block {
72 uint8_t *sl_begin, *sl_end;
75 unsigned long data_size;
79 uint8_t col, row, width, height;
83 typedef struct Palette {
85 uint8_t index[1 << 15];
88 typedef struct FlashSV2Context {
89 AVCodecContext *avctx;
90 uint8_t *current_frame;
104 int use15_7, dist, comp;
108 int64_t last_key_frame;
110 int image_width, image_height;
111 int block_width, block_height;
113 uint8_t use_custom_palette;
114 uint8_t palette_type; ///< 0=>default, 1=>custom - changed when palette regenerated.
117 #ifndef FLASHSV2_DUMB
118 double tot_blocks; ///< blocks encoded since last keyframe
119 double diff_blocks; ///< blocks that were different since last keyframe
120 double tot_lines; ///< total scanlines in image since last keyframe
121 double diff_lines; ///< scanlines that were different since last keyframe
122 double raw_size; ///< size of raw frames since last keyframe
123 double comp_size; ///< size of compressed data since last keyframe
124 double uncomp_size; ///< size of uncompressed data since last keyframe
126 double total_bits; ///< total bits written to stream so far
130 static av_cold void cleanup(FlashSV2Context * s)
132 av_freep(&s->encbuffer);
133 av_freep(&s->keybuffer);
134 av_freep(&s->databuffer);
135 av_freep(&s->blockbuffer);
136 av_freep(&s->current_frame);
137 av_freep(&s->key_frame);
139 av_freep(&s->frame_blocks);
140 av_freep(&s->key_blocks);
141 ff_deflate_end(&s->zstream);
144 static void init_blocks(FlashSV2Context * s, Block * blocks,
145 uint8_t * encbuf, uint8_t * databuf)
149 memset(blocks, 0, s->cols * s->rows * sizeof(*blocks));
150 for (col = 0; col < s->cols; col++) {
151 for (row = 0; row < s->rows; row++) {
152 b = blocks + (col + row * s->cols);
153 b->width = (col < s->cols - 1) ?
155 s->image_width - col * s->block_width;
157 b->height = (row < s->rows - 1) ?
159 s->image_height - row * s->block_height;
165 encbuf += b->width * b->height * 3;
166 databuf = databuf ? databuf + b->width * b->height * 6 : NULL;
171 static void reset_stats(FlashSV2Context * s)
173 #ifndef FLASHSV2_DUMB
174 s->diff_blocks = 0.1;
178 s->raw_size = s->comp_size = s->uncomp_size = 10;
182 static int update_block_dimensions(FlashSV2Context *s, int block_width, int block_height)
184 s->block_width = block_width;
185 s->block_height = block_height;
186 s->rows = (s->image_height + s->block_height - 1) / s->block_height;
187 s->cols = (s->image_width + s->block_width - 1) / s->block_width;
188 if (s->rows * s->cols > s->blocks_size / sizeof(Block)) {
189 s->frame_blocks = av_realloc_array(s->frame_blocks, s->rows, s->cols * sizeof(Block));
190 s->key_blocks = av_realloc_array(s->key_blocks, s->cols, s->rows * sizeof(Block));
191 if (!s->frame_blocks || !s->key_blocks) {
192 av_log(s->avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
193 return AVERROR(ENOMEM);
195 s->blocks_size = s->rows * s->cols * sizeof(Block);
197 init_blocks(s, s->frame_blocks, s->encbuffer, s->databuffer);
198 init_blocks(s, s->key_blocks, s->keybuffer, 0);
200 av_fast_malloc(&s->blockbuffer, &s->blockbuffer_size, block_width * block_height * 6);
201 if (!s->blockbuffer) {
202 av_log(s->avctx, AV_LOG_ERROR, "Could not allocate block buffer.\n");
203 return AVERROR(ENOMEM);
209 static av_cold int flashsv2_encode_init(AVCodecContext * avctx)
211 FlashSV2Context *s = avctx->priv_data;
216 s->comp = avctx->compression_level;
219 if (s->comp < 0 || s->comp > 9) {
220 av_log(avctx, AV_LOG_ERROR,
221 "Compression level should be 0-9, not %d\n", s->comp);
222 return AVERROR(EINVAL);
226 if ((avctx->width > 4095) || (avctx->height > 4095)) {
227 av_log(avctx, AV_LOG_ERROR,
228 "Input dimensions too large, input must be max 4095x4095 !\n");
229 return AVERROR(EINVAL);
231 if ((avctx->width < 16) || (avctx->height < 16)) {
232 av_log(avctx, AV_LOG_ERROR,
233 "Input dimensions too small, input must be at least 16x16 !\n");
234 return AVERROR(EINVAL);
237 if ((ret = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
240 ret = ff_deflate_init(&s->zstream, s->comp, avctx);
243 s->last_key_frame = 0;
245 s->image_width = avctx->width;
246 s->image_height = avctx->height;
248 s->frame_size = s->image_width * s->image_height * 3;
250 s->encbuffer = av_mallocz(s->frame_size);
251 s->keybuffer = av_mallocz(s->frame_size);
252 s->databuffer = av_mallocz(s->frame_size * 6);
253 s->current_frame = av_mallocz(s->frame_size);
254 s->key_frame = av_mallocz(s->frame_size);
255 if (!s->encbuffer || !s->keybuffer || !s->databuffer
256 || !s->current_frame || !s->key_frame) {
257 av_log(avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
258 return AVERROR(ENOMEM);
262 #ifndef FLASHSV2_DUMB
266 s->use_custom_palette = 0;
267 s->palette_type = -1; // so that the palette will be generated in reconfigure_at_keyframe
269 return update_block_dimensions(s, 64, 64);
272 static int new_key_frame(FlashSV2Context * s)
275 memcpy(s->key_blocks, s->frame_blocks, s->blocks_size);
276 memcpy(s->key_frame, s->current_frame, s->frame_size);
278 for (i = 0; i < s->rows * s->cols; i++) {
279 s->key_blocks[i].enc += (s->keybuffer - s->encbuffer);
280 s->key_blocks[i].sl_begin = 0;
281 s->key_blocks[i].sl_end = 0;
282 s->key_blocks[i].data = 0;
284 memcpy(s->keybuffer, s->encbuffer, s->frame_size);
289 static int write_palette(FlashSV2Context * s, uint8_t * buf, int buf_size)
291 //this isn't implemented yet! Default palette only!
295 static int write_header(FlashSV2Context * s, uint8_t * buf, int buf_size)
303 init_put_bits(&pb, buf, buf_size);
305 put_bits(&pb, 4, (s->block_width >> 4) - 1);
306 put_bits(&pb, 12, s->image_width);
307 put_bits(&pb, 4, (s->block_height >> 4) - 1);
308 put_bits(&pb, 12, s->image_height);
313 buf[buf_pos++] = s->flags;
315 if (s->flags & HAS_PALLET_INFO) {
316 len = write_palette(s, buf + buf_pos, buf_size - buf_pos);
325 static int write_block(Block * b, uint8_t * buf, int buf_size)
328 unsigned block_size = b->data_size;
330 if (b->flags & HAS_DIFF_BLOCKS)
332 if (b->flags & ZLIB_PRIME_COMPRESS_CURRENT)
336 if (buf_size < block_size + 2)
339 buf[buf_pos++] = block_size >> 8;
340 buf[buf_pos++] = block_size;
345 buf[buf_pos++] = b->flags;
347 if (b->flags & HAS_DIFF_BLOCKS) {
348 buf[buf_pos++] = (b->start);
349 buf[buf_pos++] = (b->len);
352 if (b->flags & ZLIB_PRIME_COMPRESS_CURRENT) {
353 //This feature of the format is poorly understood, and as of now, unused.
354 buf[buf_pos++] = (b->col);
355 buf[buf_pos++] = (b->row);
358 memcpy(buf + buf_pos, b->data, b->data_size);
360 buf_pos += b->data_size;
365 static int encode_zlib(Block *b, uint8_t *buf, unsigned long *buf_size,
370 if (deflateReset(zstream) != Z_OK)
371 return AVERROR_EXTERNAL;
372 zstream->next_out = buf;
373 zstream->avail_out = *buf_size;
374 zstream->next_in = b->sl_begin;
375 zstream->avail_in = b->sl_end - b->sl_begin;
376 res = deflate(zstream, Z_FINISH);
377 if (res != Z_STREAM_END)
378 return AVERROR_EXTERNAL;
379 *buf_size -= zstream->avail_out;
383 static int encode_zlibprime(Block * b, Block * prime, uint8_t * buf,
384 int *buf_size, z_stream *zstream)
388 if (deflateReset(zstream) != Z_OK)
389 return AVERROR_EXTERNAL;
390 zstream->next_in = prime->enc;
391 zstream->avail_in = prime->enc_size;
392 while (zstream->avail_in > 0) {
393 zstream->next_out = buf;
394 zstream->avail_out = *buf_size;
395 res = deflate(zstream, Z_SYNC_FLUSH);
400 zstream->next_in = b->sl_begin;
401 zstream->avail_in = b->sl_end - b->sl_begin;
402 zstream->next_out = buf;
403 zstream->avail_out = *buf_size;
404 res = deflate(zstream, Z_FINISH);
405 *buf_size -= zstream->avail_out;
406 if (res != Z_STREAM_END)
411 static int encode_bgr(Block * b, const uint8_t * src, int stride)
414 uint8_t *ptr = b->enc;
415 for (i = 0; i < b->start; i++)
416 memcpy(ptr + i * b->width * 3, src + i * stride, b->width * 3);
417 b->sl_begin = ptr + i * b->width * 3;
418 for (; i < b->start + b->len; i++)
419 memcpy(ptr + i * b->width * 3, src + i * stride, b->width * 3);
420 b->sl_end = ptr + i * b->width * 3;
421 for (; i < b->height; i++)
422 memcpy(ptr + i * b->width * 3, src + i * stride, b->width * 3);
423 b->enc_size = ptr + i * b->width * 3 - b->enc;
427 static inline unsigned pixel_color15(const uint8_t * src)
429 return (src[0] >> 3) | ((src[1] & 0xf8) << 2) | ((src[2] & 0xf8) << 7);
432 static inline unsigned int chroma_diff(unsigned int c1, unsigned int c2)
434 #define ABSDIFF(a,b) (abs((int)(a)-(int)(b)))
436 unsigned int t1 = (c1 & 0x000000ff) + ((c1 & 0x0000ff00) >> 8) + ((c1 & 0x00ff0000) >> 16);
437 unsigned int t2 = (c2 & 0x000000ff) + ((c2 & 0x0000ff00) >> 8) + ((c2 & 0x00ff0000) >> 16);
439 return ABSDIFF(t1, t2) + ABSDIFF(c1 & 0x000000ff, c2 & 0x000000ff) +
440 ABSDIFF((c1 & 0x0000ff00) >> 8 , (c2 & 0x0000ff00) >> 8) +
441 ABSDIFF((c1 & 0x00ff0000) >> 16, (c2 & 0x00ff0000) >> 16);
444 static inline int pixel_color7_fast(Palette * palette, unsigned c15)
446 return palette->index[c15];
449 static int pixel_color7_slow(Palette * palette, unsigned color)
451 int i, min = 0x7fffffff;
453 for (i = 0; i < 128; i++) {
454 int c1 = palette->colors[i];
455 int diff = chroma_diff(c1, color);
464 static inline unsigned pixel_bgr(const uint8_t * src)
466 return (src[0]) | (src[1] << 8) | (src[2] << 16);
469 static int write_pixel_15_7(Palette * palette, uint8_t * dest, const uint8_t * src,
472 unsigned c15 = pixel_color15(src);
473 unsigned color = pixel_bgr(src);
474 int d15 = chroma_diff(color, color & 0x00f8f8f8);
475 int c7 = pixel_color7_fast(palette, c15);
476 int d7 = chroma_diff(color, palette->colors[c7]);
477 if (dist + d15 >= d7) {
481 dest[0] = 0x80 | (c15 >> 8);
482 dest[1] = c15 & 0xff;
487 static int update_palette_index(Palette * palette)
490 unsigned int bgr, c15, index;
491 for (r = 4; r < 256; r += 8) {
492 for (g = 4; g < 256; g += 8) {
493 for (b = 4; b < 256; b += 8) {
494 bgr = b | (g << 8) | (r << 16);
495 c15 = (b >> 3) | ((g & 0xf8) << 2) | ((r & 0xf8) << 7);
496 index = pixel_color7_slow(palette, bgr);
498 palette->index[c15] = index;
505 static const unsigned int default_screen_video_v2_palette[128] = {
506 0x00000000, 0x00333333, 0x00666666, 0x00999999, 0x00CCCCCC, 0x00FFFFFF,
507 0x00330000, 0x00660000, 0x00990000, 0x00CC0000, 0x00FF0000, 0x00003300,
508 0x00006600, 0x00009900, 0x0000CC00, 0x0000FF00, 0x00000033, 0x00000066,
509 0x00000099, 0x000000CC, 0x000000FF, 0x00333300, 0x00666600, 0x00999900,
510 0x00CCCC00, 0x00FFFF00, 0x00003333, 0x00006666, 0x00009999, 0x0000CCCC,
511 0x0000FFFF, 0x00330033, 0x00660066, 0x00990099, 0x00CC00CC, 0x00FF00FF,
512 0x00FFFF33, 0x00FFFF66, 0x00FFFF99, 0x00FFFFCC, 0x00FF33FF, 0x00FF66FF,
513 0x00FF99FF, 0x00FFCCFF, 0x0033FFFF, 0x0066FFFF, 0x0099FFFF, 0x00CCFFFF,
514 0x00CCCC33, 0x00CCCC66, 0x00CCCC99, 0x00CCCCFF, 0x00CC33CC, 0x00CC66CC,
515 0x00CC99CC, 0x00CCFFCC, 0x0033CCCC, 0x0066CCCC, 0x0099CCCC, 0x00FFCCCC,
516 0x00999933, 0x00999966, 0x009999CC, 0x009999FF, 0x00993399, 0x00996699,
517 0x0099CC99, 0x0099FF99, 0x00339999, 0x00669999, 0x00CC9999, 0x00FF9999,
518 0x00666633, 0x00666699, 0x006666CC, 0x006666FF, 0x00663366, 0x00669966,
519 0x0066CC66, 0x0066FF66, 0x00336666, 0x00996666, 0x00CC6666, 0x00FF6666,
520 0x00333366, 0x00333399, 0x003333CC, 0x003333FF, 0x00336633, 0x00339933,
521 0x0033CC33, 0x0033FF33, 0x00663333, 0x00993333, 0x00CC3333, 0x00FF3333,
522 0x00003366, 0x00336600, 0x00660033, 0x00006633, 0x00330066, 0x00663300,
523 0x00336699, 0x00669933, 0x00993366, 0x00339966, 0x00663399, 0x00996633,
524 0x006699CC, 0x0099CC66, 0x00CC6699, 0x0066CC99, 0x009966CC, 0x00CC9966,
525 0x0099CCFF, 0x00CCFF99, 0x00FF99CC, 0x0099FFCC, 0x00CC99FF, 0x00FFCC99,
526 0x00111111, 0x00222222, 0x00444444, 0x00555555, 0x00AAAAAA, 0x00BBBBBB,
527 0x00DDDDDD, 0x00EEEEEE
530 static int generate_default_palette(Palette * palette)
532 memcpy(palette->colors, default_screen_video_v2_palette,
533 sizeof(default_screen_video_v2_palette));
535 return update_palette_index(palette);
538 static int generate_optimum_palette(Palette * palette, const uint8_t * image,
539 int width, int height, int stride)
541 //this isn't implemented yet! Default palette only!
545 static inline int encode_15_7_sl(Palette * palette, uint8_t * dest,
546 const uint8_t * src, int width, int dist)
549 for (x = 0; x < width; x++) {
550 len += write_pixel_15_7(palette, dest + len, src + 3 * x, dist);
555 static int encode_15_7(Palette * palette, Block * b, const uint8_t * src,
556 int stride, int dist)
559 uint8_t *ptr = b->enc;
560 for (i = 0; i < b->start; i++)
561 ptr += encode_15_7_sl(palette, ptr, src + i * stride, b->width, dist);
563 for (; i < b->start + b->len; i++)
564 ptr += encode_15_7_sl(palette, ptr, src + i * stride, b->width, dist);
566 for (; i < b->height; i++)
567 ptr += encode_15_7_sl(palette, ptr, src + i * stride, b->width, dist);
568 b->enc_size = ptr - b->enc;
572 static int encode_block(FlashSV2Context *s, Palette * palette, Block * b,
573 Block *prev, const uint8_t *src, int stride,
574 int dist, int keyframe)
576 unsigned buf_size = b->width * b->height * 6;
577 uint8_t *buf = s->blockbuffer;
580 if (b->flags & COLORSPACE_15_7) {
581 encode_15_7(palette, b, src, stride, dist);
583 encode_bgr(b, src, stride);
587 b->data_size = buf_size;
588 res = encode_zlib(b, b->data, &b->data_size, &s->zstream.zstream);
593 res = encode_zlibprime(b, prev, buf, &buf_size, &s->zstream.zstream);
597 if (buf_size < b->data_size) {
598 b->data_size = buf_size;
599 memcpy(b->data, buf, buf_size);
600 b->flags |= ZLIB_PRIME_COMPRESS_PREVIOUS;
609 static int compare_sl(FlashSV2Context * s, Block * b, const uint8_t * src,
610 uint8_t * frame, uint8_t * key, int y, int keyframe)
612 if (memcmp(src, frame, b->width * 3) != 0) {
614 memcpy(frame, src, b->width * 3);
615 #ifndef FLASHSV2_DUMB
619 if (memcmp(src, key, b->width * 3) != 0) {
622 b->len = y + 1 - b->start;
627 static int mark_all_blocks(FlashSV2Context * s, const uint8_t * src, int stride,
630 int sl, rsl, col, pos, possl;
632 for (sl = s->image_height - 1; sl >= 0; sl--) {
633 for (col = 0; col < s->cols; col++) {
634 rsl = s->image_height - sl - 1;
635 b = s->frame_blocks + col + rsl / s->block_height * s->cols;
636 possl = stride * sl + col * s->block_width * 3;
637 pos = s->image_width * rsl * 3 + col * s->block_width * 3;
638 compare_sl(s, b, src + possl, s->current_frame + pos,
639 s->key_frame + pos, rsl % s->block_height, keyframe);
642 #ifndef FLASHSV2_DUMB
643 s->tot_lines += s->image_height * s->cols;
648 static int encode_all_blocks(FlashSV2Context * s, int keyframe)
653 for (row = 0; row < s->rows; row++) {
654 for (col = 0; col < s->cols; col++) {
655 b = s->frame_blocks + (row * s->cols + col);
656 prev = s->key_blocks + (row * s->cols + col);
657 b->flags = s->use15_7 ? COLORSPACE_15_7 : 0;
661 } else if (!b->dirty) {
666 } else if (b->start != 0 || b->len != b->height) {
667 b->flags |= HAS_DIFF_BLOCKS;
669 data = s->current_frame + s->image_width * 3 * s->block_height * row + s->block_width * col * 3;
670 res = encode_block(s, &s->palette, b, prev, data,
671 s->image_width * 3, s->dist, keyframe);
672 #ifndef FLASHSV2_DUMB
675 s->comp_size += b->data_size;
676 s->uncomp_size += b->enc_size;
682 #ifndef FLASHSV2_DUMB
683 s->raw_size += s->image_width * s->image_height * 3;
684 s->tot_blocks += s->rows * s->cols;
689 static int write_all_blocks(FlashSV2Context * s, uint8_t * buf,
692 int row, col, buf_pos = 0, len;
694 for (row = 0; row < s->rows; row++) {
695 for (col = 0; col < s->cols; col++) {
696 b = s->frame_blocks + row * s->cols + col;
697 len = write_block(b, buf + buf_pos, buf_size - buf_pos);
698 b->start = b->len = b->dirty = 0;
707 static int write_bitstream(FlashSV2Context * s, const uint8_t * src, int stride,
708 uint8_t * buf, int buf_size, int keyframe)
712 res = mark_all_blocks(s, src, stride, keyframe);
715 res = encode_all_blocks(s, keyframe);
719 res = write_header(s, buf, buf_size);
725 res = write_all_blocks(s, buf + buf_pos, buf_size - buf_pos);
729 #ifndef FLASHSV2_DUMB
730 s->total_bits += ((double) buf_pos) * 8.0;
736 static void recommend_keyframe(FlashSV2Context * s, int *keyframe)
738 #ifndef FLASHSV2_DUMB
739 double block_ratio, line_ratio, enc_ratio, comp_ratio, data_ratio;
740 if (s->avctx->gop_size > 0) {
741 block_ratio = s->diff_blocks / s->tot_blocks;
742 line_ratio = s->diff_lines / s->tot_lines;
743 enc_ratio = s->uncomp_size / s->raw_size;
744 comp_ratio = s->comp_size / s->uncomp_size;
745 data_ratio = s->comp_size / s->raw_size;
747 if ((block_ratio >= 0.5 && line_ratio / block_ratio <= 0.5) || line_ratio >= 0.95) {
757 #ifndef FLASHSV2_DUMB
758 static const double block_size_fraction = 1.0 / 300;
759 static const double use15_7_threshold = 8192;
760 static const double color15_7_factor = 100;
762 static int optimum_block_width(FlashSV2Context * s)
764 #ifndef FLASHSV2_DUMB
765 double save = (1-pow(s->diff_lines/s->diff_blocks/s->block_height, 0.5)) * s->comp_size/s->tot_blocks;
766 double width = block_size_fraction * sqrt(0.5 * save * s->rows * s->cols) * s->image_width;
767 int pwidth = ((int) width);
768 return FFCLIP(pwidth & ~15, 256, 16);
774 static int optimum_block_height(FlashSV2Context * s)
776 #ifndef FLASHSV2_DUMB
777 double save = (1-pow(s->diff_lines/s->diff_blocks/s->block_height, 0.5)) * s->comp_size/s->tot_blocks;
778 double height = block_size_fraction * sqrt(0.5 * save * s->rows * s->cols) * s->image_height;
779 int pheight = ((int) height);
780 return FFCLIP(pheight & ~15, 256, 16);
786 static int optimum_use15_7(FlashSV2Context * s)
788 #ifndef FLASHSV2_DUMB
789 double ideal = ((double)(s->avctx->bit_rate * s->avctx->time_base.den * s->avctx->ticks_per_frame)) /
790 ((double) s->avctx->time_base.num) * s->avctx->frame_num;
791 if (ideal + use15_7_threshold < s->total_bits) {
797 return s->avctx->global_quality == 0;
801 static int optimum_dist(FlashSV2Context * s)
803 #ifndef FLASHSV2_DUMB
805 s->avctx->bit_rate * s->avctx->time_base.den *
806 s->avctx->ticks_per_frame;
807 int dist = pow((s->total_bits / ideal) * color15_7_factor, 3);
808 av_log(s->avctx, AV_LOG_DEBUG, "dist: %d\n", dist);
816 static int reconfigure_at_keyframe(FlashSV2Context * s, const uint8_t * image,
819 int update_palette = 0;
821 int block_width = optimum_block_width (s);
822 int block_height = optimum_block_height(s);
824 if (block_width != s->block_width || block_height != s->block_height) {
825 res = update_block_dimensions(s, block_width, block_height);
830 s->use15_7 = optimum_use15_7(s);
832 if ((s->use_custom_palette && s->palette_type != 1) || update_palette) {
833 res = generate_optimum_palette(&s->palette, image, s->image_width, s->image_height, stride);
837 av_log(s->avctx, AV_LOG_DEBUG, "Generated optimum palette\n");
838 } else if (!s->use_custom_palette && s->palette_type != 0) {
839 res = generate_default_palette(&s->palette);
843 av_log(s->avctx, AV_LOG_DEBUG, "Generated default palette\n");
853 static int flashsv2_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
854 const AVFrame *p, int *got_packet)
856 FlashSV2Context *const s = avctx->priv_data;
860 if ((res = ff_alloc_packet(avctx, pkt, s->frame_size + AV_INPUT_BUFFER_MIN_SIZE)) < 0)
863 /* First frame needs to be a keyframe */
864 if (avctx->frame_num == 0)
867 /* Check the placement of keyframes */
868 if (avctx->gop_size > 0) {
869 if (avctx->frame_num >= s->last_key_frame + avctx->gop_size)
874 && avctx->frame_num > s->last_key_frame + avctx->keyint_min) {
875 recommend_keyframe(s, &keyframe);
877 av_log(avctx, AV_LOG_DEBUG, "Recommending key frame at frame %"PRId64"\n", avctx->frame_num);
881 res = reconfigure_at_keyframe(s, p->data[0], p->linesize[0]);
887 s->dist = optimum_dist(s);
889 res = write_bitstream(s, p->data[0], p->linesize[0], pkt->data, pkt->size, keyframe);
893 s->last_key_frame = avctx->frame_num;
894 pkt->flags |= AV_PKT_FLAG_KEY;
895 av_log(avctx, AV_LOG_DEBUG, "Inserting key frame at frame %"PRId64"\n", avctx->frame_num);
904 static av_cold int flashsv2_encode_end(AVCodecContext * avctx)
906 FlashSV2Context *s = avctx->priv_data;
913 const FFCodec ff_flashsv2_encoder = {
914 .p.name = "flashsv2",
915 CODEC_LONG_NAME("Flash Screen Video Version 2"),
916 .p.type = AVMEDIA_TYPE_VIDEO,
917 .p.id = AV_CODEC_ID_FLASHSV2,
918 .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_ENCODER_REORDERED_OPAQUE,
919 .priv_data_size = sizeof(FlashSV2Context),
920 .init = flashsv2_encode_init,
921 FF_CODEC_ENCODE_CB(flashsv2_encode_frame),
922 .close = flashsv2_encode_end,
923 .p.pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
924 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,