2 * Flash Screen Video decoder
3 * Copyright (C) 2004 Alex Beregszaszi
4 * Copyright (C) 2006 Benjamin Larsson
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
25 * Flash Screen Video decoder
26 * @author Alex Beregszaszi
27 * @author Benjamin Larsson
28 * @author Daniel Verkamp
29 * @author Konstantin Shishkov
31 * A description of the bitstream format for Flash Screen Video version 1/2
32 * is part of the SWF File Format Specification (version 10), which can be
33 * downloaded from http://www.adobe.com/devnet/swf.html.
40 #include "libavutil/intreadwrite.h"
42 #include "bytestream.h"
45 typedef struct BlockInfo {
50 typedef struct FlashSVContext {
51 AVCodecContext *avctx;
53 int image_width, image_height;
54 int block_width, block_height;
61 uint8_t *keyframedata;
64 uint8_t *deflate_block;
65 int deflate_block_size;
67 int zlibprime_curr, zlibprime_prev;
68 int diff_start, diff_height;
72 static int decode_hybrid(const uint8_t *sptr, uint8_t *dptr, int dx, int dy,
73 int h, int w, int stride, const uint32_t *pal)
76 const uint8_t *orig_src = sptr;
78 for (y = dx+h; y > dx; y--) {
79 uint8_t *dst = dptr + (y * stride) + dy * 3;
80 for (x = 0; x < w; x++) {
83 unsigned c = AV_RB16(sptr) & ~0x8000;
84 unsigned b = c & 0x1F;
85 unsigned g = (c >> 5) & 0x1F;
87 /* 000aaabb -> aaabbaaa */
88 *dst++ = (b << 3) | (b >> 2);
89 *dst++ = (g << 3) | (g >> 2);
90 *dst++ = (r << 3) | (r >> 2);
94 uint32_t c = pal[*sptr++];
95 bytestream_put_le24(&dst, c);
99 return sptr - orig_src;
102 static av_cold int flashsv_decode_init(AVCodecContext *avctx)
104 FlashSVContext *s = avctx->priv_data;
105 int zret; // Zlib return code
108 s->zstream.zalloc = Z_NULL;
109 s->zstream.zfree = Z_NULL;
110 s->zstream.opaque = Z_NULL;
111 zret = inflateInit(&s->zstream);
113 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
116 avctx->pix_fmt = AV_PIX_FMT_BGR24;
117 avcodec_get_frame_defaults(&s->frame);
118 s->frame.data[0] = NULL;
124 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
127 int zret; // Zlib return code
133 s->zstream.next_in = src;
134 s->zstream.avail_in = size;
135 s->zstream.next_out = s->tmpblock;
136 s->zstream.avail_out = s->block_size * 3;
137 inflate(&s->zstream, Z_SYNC_FLUSH);
139 if (deflateInit(&zs, 0) != Z_OK)
141 zs.next_in = s->tmpblock;
142 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
143 zs.next_out = s->deflate_block;
144 zs.avail_out = s->deflate_block_size;
145 deflate(&zs, Z_SYNC_FLUSH);
148 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
149 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
150 return AVERROR_UNKNOWN;
153 s->zstream.next_in = s->deflate_block;
154 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
155 s->zstream.next_out = s->tmpblock;
156 s->zstream.avail_out = s->block_size * 3;
157 inflate(&s->zstream, Z_SYNC_FLUSH);
162 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
163 GetBitContext *gb, int block_size,
164 int width, int height, int x_pos, int y_pos,
167 struct FlashSVContext *s = avctx->priv_data;
168 uint8_t *line = s->tmpblock;
170 int ret = inflateReset(&s->zstream);
172 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
173 return AVERROR_UNKNOWN;
175 if (s->zlibprime_curr || s->zlibprime_prev) {
176 ret = flashsv2_prime(s,
177 s->blocks[blk_idx].pos,
178 s->blocks[blk_idx].size);
182 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
183 s->zstream.avail_in = block_size;
184 s->zstream.next_out = s->tmpblock;
185 s->zstream.avail_out = s->block_size * 3;
186 ret = inflate(&s->zstream, Z_FINISH);
187 if (ret == Z_DATA_ERROR) {
188 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
189 inflateSync(&s->zstream);
190 ret = inflate(&s->zstream, Z_FINISH);
193 if (ret != Z_OK && ret != Z_STREAM_END) {
197 if (s->is_keyframe) {
198 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
199 s->blocks[blk_idx].size = block_size;
201 if (!s->color_depth) {
202 /* Flash Screen Video stores the image upside down, so copy
203 * lines to destination in reverse order. */
204 for (k = 1; k <= s->diff_height; k++) {
205 memcpy(s->frame.data[0] + x_pos * 3 +
206 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
208 /* advance source pointer to next line */
212 /* hybrid 15-bit/palette mode */
213 decode_hybrid(s->tmpblock, s->frame.data[0],
214 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
215 x_pos, s->diff_height, width,
216 s->frame.linesize[0], s->pal);
218 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
222 static int calc_deflate_block_size(int tmpblock_size)
227 zstream.zalloc = Z_NULL;
228 zstream.zfree = Z_NULL;
229 zstream.opaque = Z_NULL;
230 if (deflateInit(&zstream, 0) != Z_OK)
232 size = deflateBound(&zstream, tmpblock_size);
233 deflateEnd(&zstream);
238 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
239 int *data_size, AVPacket *avpkt)
241 int buf_size = avpkt->size;
242 FlashSVContext *s = avctx->priv_data;
243 int h_blocks, v_blocks, h_part, v_part, i, j;
246 /* no supplementary picture */
252 init_get_bits(&gb, avpkt->data, buf_size * 8);
254 /* start to parse the bitstream */
255 s->block_width = 16 * (get_bits(&gb, 4) + 1);
256 s->image_width = get_bits(&gb, 12);
257 s->block_height = 16 * (get_bits(&gb, 4) + 1);
258 s->image_height = get_bits(&gb, 12);
262 if (get_bits1(&gb)) {
263 av_log_missing_feature(avctx, "iframe", 1);
264 return AVERROR_PATCHWELCOME;
266 if (get_bits1(&gb)) {
267 av_log_missing_feature(avctx, "Custom palette", 1);
268 return AVERROR_PATCHWELCOME;
272 /* calculate number of blocks and size of border (partial) blocks */
273 h_blocks = s->image_width / s->block_width;
274 h_part = s->image_width % s->block_width;
275 v_blocks = s->image_height / s->block_height;
276 v_part = s->image_height % s->block_height;
278 /* the block size could change between frames, make sure the buffer
279 * is large enough, if not, get a larger one */
280 if (s->block_size < s->block_width * s->block_height) {
281 int tmpblock_size = 3 * s->block_width * s->block_height;
283 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
285 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
286 return AVERROR(ENOMEM);
289 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
290 if (s->deflate_block_size <= 0) {
291 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
294 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
295 if (!s->deflate_block) {
296 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
297 return AVERROR(ENOMEM);
301 s->block_size = s->block_width * s->block_height;
303 /* initialize the image size once */
304 if (avctx->width == 0 && avctx->height == 0) {
305 avcodec_set_dimensions(avctx, s->image_width, s->image_height);
308 /* check for changes of image width and image height */
309 if (avctx->width != s->image_width || avctx->height != s->image_height) {
310 av_log(avctx, AV_LOG_ERROR,
311 "Frame width or height differs from first frame!\n");
312 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
313 avctx->height, avctx->width, s->image_height, s->image_width);
314 return AVERROR_INVALIDDATA;
317 /* we care for keyframes only in Screen Video v2 */
318 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
319 if (s->is_keyframe) {
320 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
321 memcpy(s->keyframedata, avpkt->data, avpkt->size);
324 s->blocks = av_realloc(s->blocks,
325 (v_blocks + !!v_part) * (h_blocks + !!h_part)
326 * sizeof(s->blocks[0]));
328 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
329 s->image_width, s->image_height, s->block_width, s->block_height,
330 h_blocks, v_blocks, h_part, v_part);
332 s->frame.reference = 3;
333 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
334 FF_BUFFER_HINTS_PRESERVE |
335 FF_BUFFER_HINTS_REUSABLE;
336 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
337 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
341 /* loop over all block columns */
342 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
344 int y_pos = j * s->block_height; // vertical position in frame
345 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
347 /* loop over all block rows */
348 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
349 int x_pos = i * s->block_width; // horizontal position in frame
350 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
353 /* get the size of the compressed zlib chunk */
354 int size = get_bits(&gb, 16);
357 s->zlibprime_curr = 0;
358 s->zlibprime_prev = 0;
360 s->diff_height = cur_blk_height;
362 if (8 * size > get_bits_left(&gb)) {
363 avctx->release_buffer(avctx, &s->frame);
364 s->frame.data[0] = NULL;
365 return AVERROR_INVALIDDATA;
368 if (s->ver == 2 && size) {
370 s->color_depth = get_bits(&gb, 2);
371 has_diff = get_bits1(&gb);
372 s->zlibprime_curr = get_bits1(&gb);
373 s->zlibprime_prev = get_bits1(&gb);
375 if (s->color_depth != 0 && s->color_depth != 2) {
376 av_log(avctx, AV_LOG_ERROR,
377 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
378 return AVERROR_INVALIDDATA;
383 av_log(avctx, AV_LOG_ERROR,
384 "inter frame without keyframe\n");
385 return AVERROR_INVALIDDATA;
387 s->diff_start = get_bits(&gb, 8);
388 s->diff_height = get_bits(&gb, 8);
389 av_log(avctx, AV_LOG_DEBUG,
390 "%dx%d diff start %d height %d\n",
391 i, j, s->diff_start, s->diff_height);
395 if (s->zlibprime_prev)
396 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
398 if (s->zlibprime_curr) {
399 int col = get_bits(&gb, 8);
400 int row = get_bits(&gb, 8);
401 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
403 av_log_missing_feature(avctx, "zlibprime_curr", 1);
404 return AVERROR_PATCHWELCOME;
406 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
407 av_log(avctx, AV_LOG_ERROR, "no data available for zlib "
409 return AVERROR_INVALIDDATA;
411 size--; // account for flags byte
416 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
418 for (k = 0; k < cur_blk_height; k++)
419 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
420 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
424 /* skip unchanged blocks, which have size 0 */
426 if (flashsv_decode_block(avctx, avpkt, &gb, size,
427 cur_blk_width, cur_blk_height,
429 i + j * (h_blocks + !!h_part)))
430 av_log(avctx, AV_LOG_ERROR,
431 "error in decompression of block %dx%d\n", i, j);
435 if (s->is_keyframe && s->ver == 2) {
437 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
439 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
440 return AVERROR(ENOMEM);
443 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
446 *data_size = sizeof(AVFrame);
447 *(AVFrame*)data = s->frame;
449 if ((get_bits_count(&gb) / 8) != buf_size)
450 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
451 buf_size, (get_bits_count(&gb) / 8));
453 /* report that the buffer was completely consumed */
458 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
460 FlashSVContext *s = avctx->priv_data;
461 inflateEnd(&s->zstream);
462 /* release the frame if needed */
463 if (s->frame.data[0])
464 avctx->release_buffer(avctx, &s->frame);
466 /* free the tmpblock */
467 av_free(s->tmpblock);
473 #if CONFIG_FLASHSV_DECODER
474 AVCodec ff_flashsv_decoder = {
476 .type = AVMEDIA_TYPE_VIDEO,
477 .id = AV_CODEC_ID_FLASHSV,
478 .priv_data_size = sizeof(FlashSVContext),
479 .init = flashsv_decode_init,
480 .close = flashsv_decode_end,
481 .decode = flashsv_decode_frame,
482 .capabilities = CODEC_CAP_DR1,
483 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
484 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
486 #endif /* CONFIG_FLASHSV_DECODER */
488 #if CONFIG_FLASHSV2_DECODER
489 static const uint32_t ff_flashsv2_default_palette[128] = {
490 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
491 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
492 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
493 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
494 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
495 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
496 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
497 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
498 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
499 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
500 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
501 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
502 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
503 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
504 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
505 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
506 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
507 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
508 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
509 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
510 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
514 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
516 FlashSVContext *s = avctx->priv_data;
517 flashsv_decode_init(avctx);
518 s->pal = ff_flashsv2_default_palette;
524 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
526 FlashSVContext *s = avctx->priv_data;
528 av_freep(&s->keyframedata);
529 av_freep(&s->blocks);
530 av_freep(&s->keyframe);
531 av_freep(&s->deflate_block);
532 flashsv_decode_end(avctx);
537 AVCodec ff_flashsv2_decoder = {
539 .type = AVMEDIA_TYPE_VIDEO,
540 .id = AV_CODEC_ID_FLASHSV2,
541 .priv_data_size = sizeof(FlashSVContext),
542 .init = flashsv2_decode_init,
543 .close = flashsv2_decode_end,
544 .decode = flashsv_decode_frame,
545 .capabilities = CODEC_CAP_DR1,
546 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
547 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
549 #endif /* CONFIG_FLASHSV2_DECODER */