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"
46 typedef struct BlockInfo {
51 typedef struct FlashSVContext {
52 AVCodecContext *avctx;
54 int image_width, image_height;
55 int block_width, block_height;
62 uint8_t *keyframedata;
65 uint8_t *deflate_block;
66 int deflate_block_size;
68 int zlibprime_curr, zlibprime_prev;
69 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);
122 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
125 int zret; // Zlib return code
128 return AVERROR_INVALIDDATA;
134 s->zstream.next_in = src;
135 s->zstream.avail_in = size;
136 s->zstream.next_out = s->tmpblock;
137 s->zstream.avail_out = s->block_size * 3;
138 inflate(&s->zstream, Z_SYNC_FLUSH);
140 if (deflateInit(&zs, 0) != Z_OK)
142 zs.next_in = s->tmpblock;
143 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
144 zs.next_out = s->deflate_block;
145 zs.avail_out = s->deflate_block_size;
146 deflate(&zs, Z_SYNC_FLUSH);
149 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
150 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
151 return AVERROR_UNKNOWN;
154 s->zstream.next_in = s->deflate_block;
155 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
156 s->zstream.next_out = s->tmpblock;
157 s->zstream.avail_out = s->block_size * 3;
158 inflate(&s->zstream, Z_SYNC_FLUSH);
163 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
164 GetBitContext *gb, int block_size,
165 int width, int height, int x_pos, int y_pos,
168 struct FlashSVContext *s = avctx->priv_data;
169 uint8_t *line = s->tmpblock;
171 int ret = inflateReset(&s->zstream);
173 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
174 return AVERROR_UNKNOWN;
176 if (s->zlibprime_curr || s->zlibprime_prev) {
177 ret = flashsv2_prime(s,
178 s->blocks[blk_idx].pos,
179 s->blocks[blk_idx].size);
183 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
184 s->zstream.avail_in = block_size;
185 s->zstream.next_out = s->tmpblock;
186 s->zstream.avail_out = s->block_size * 3;
187 ret = inflate(&s->zstream, Z_FINISH);
188 if (ret == Z_DATA_ERROR) {
189 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
190 inflateSync(&s->zstream);
191 ret = inflate(&s->zstream, Z_FINISH);
194 if (ret != Z_OK && ret != Z_STREAM_END) {
198 if (s->is_keyframe) {
199 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
200 s->blocks[blk_idx].size = block_size;
203 y_pos += s->diff_start;
205 if (!s->color_depth) {
206 /* Flash Screen Video stores the image upside down, so copy
207 * lines to destination in reverse order. */
208 for (k = 1; k <= s->diff_height; k++) {
209 memcpy(s->frame.data[0] + x_pos * 3 +
210 (s->image_height - y_pos - k) * s->frame.linesize[0],
212 /* advance source pointer to next line */
216 /* hybrid 15-bit/palette mode */
217 decode_hybrid(s->tmpblock, s->frame.data[0],
218 s->image_height - (y_pos + 1 + s->diff_height),
219 x_pos, s->diff_height, width,
220 s->frame.linesize[0], s->pal);
222 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
226 static int calc_deflate_block_size(int tmpblock_size)
231 zstream.zalloc = Z_NULL;
232 zstream.zfree = Z_NULL;
233 zstream.opaque = Z_NULL;
234 if (deflateInit(&zstream, 0) != Z_OK)
236 size = deflateBound(&zstream, tmpblock_size);
237 deflateEnd(&zstream);
242 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
243 int *got_frame, AVPacket *avpkt)
245 int buf_size = avpkt->size;
246 FlashSVContext *s = avctx->priv_data;
247 int h_blocks, v_blocks, h_part, v_part, i, j, ret;
249 int last_blockwidth = s->block_width;
250 int last_blockheight= s->block_height;
252 /* no supplementary picture */
258 init_get_bits(&gb, avpkt->data, buf_size * 8);
260 /* start to parse the bitstream */
261 s->block_width = 16 * (get_bits(&gb, 4) + 1);
262 s->image_width = get_bits(&gb, 12);
263 s->block_height = 16 * (get_bits(&gb, 4) + 1);
264 s->image_height = get_bits(&gb, 12);
266 if ( last_blockwidth != s->block_width
267 || last_blockheight!= s->block_height)
268 av_freep(&s->blocks);
272 if (get_bits1(&gb)) {
273 avpriv_request_sample(avctx, "iframe");
274 return AVERROR_PATCHWELCOME;
276 if (get_bits1(&gb)) {
277 avpriv_request_sample(avctx, "Custom palette");
278 return AVERROR_PATCHWELCOME;
282 /* calculate number of blocks and size of border (partial) blocks */
283 h_blocks = s->image_width / s->block_width;
284 h_part = s->image_width % s->block_width;
285 v_blocks = s->image_height / s->block_height;
286 v_part = s->image_height % s->block_height;
288 /* the block size could change between frames, make sure the buffer
289 * is large enough, if not, get a larger one */
290 if (s->block_size < s->block_width * s->block_height) {
291 int tmpblock_size = 3 * s->block_width * s->block_height;
293 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
295 av_log(avctx, AV_LOG_ERROR,
296 "Cannot allocate decompression buffer.\n");
297 return AVERROR(ENOMEM);
300 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
301 if (s->deflate_block_size <= 0) {
302 av_log(avctx, AV_LOG_ERROR,
303 "Cannot determine deflate buffer size.\n");
306 s->deflate_block = av_realloc(s->deflate_block,
307 s->deflate_block_size);
308 if (!s->deflate_block) {
309 av_log(avctx, AV_LOG_ERROR,
310 "Cannot allocate deflate buffer.\n");
311 return AVERROR(ENOMEM);
315 s->block_size = s->block_width * s->block_height;
317 /* initialize the image size once */
318 if (avctx->width == 0 && avctx->height == 0) {
319 avcodec_set_dimensions(avctx, s->image_width, s->image_height);
322 /* check for changes of image width and image height */
323 if (avctx->width != s->image_width || avctx->height != s->image_height) {
324 av_log(avctx, AV_LOG_ERROR,
325 "Frame width or height differs from first frame!\n");
326 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
327 avctx->height, avctx->width, s->image_height, s->image_width);
328 return AVERROR_INVALIDDATA;
331 /* we care for keyframes only in Screen Video v2 */
332 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
333 if (s->is_keyframe) {
334 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
335 memcpy(s->keyframedata, avpkt->data, avpkt->size);
337 if(s->ver == 2 && !s->blocks)
338 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part) *
339 sizeof(s->blocks[0]));
341 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
342 s->image_width, s->image_height, s->block_width, s->block_height,
343 h_blocks, v_blocks, h_part, v_part);
345 if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
348 /* loop over all block columns */
349 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
351 int y_pos = j * s->block_height; // vertical position in frame
352 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
354 /* loop over all block rows */
355 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
356 int x_pos = i * s->block_width; // horizontal position in frame
357 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
360 /* get the size of the compressed zlib chunk */
361 int size = get_bits(&gb, 16);
364 s->zlibprime_curr = 0;
365 s->zlibprime_prev = 0;
367 s->diff_height = cur_blk_height;
369 if (8 * size > get_bits_left(&gb)) {
370 av_frame_unref(&s->frame);
371 return AVERROR_INVALIDDATA;
374 if (s->ver == 2 && size) {
376 s->color_depth = get_bits(&gb, 2);
377 has_diff = get_bits1(&gb);
378 s->zlibprime_curr = get_bits1(&gb);
379 s->zlibprime_prev = get_bits1(&gb);
381 if (s->color_depth != 0 && s->color_depth != 2) {
382 av_log(avctx, AV_LOG_ERROR,
383 "%dx%d invalid color depth %d\n",
384 i, j, s->color_depth);
385 return AVERROR_INVALIDDATA;
390 av_log(avctx, AV_LOG_ERROR,
391 "Inter frame without keyframe\n");
392 return AVERROR_INVALIDDATA;
394 s->diff_start = get_bits(&gb, 8);
395 s->diff_height = get_bits(&gb, 8);
396 if (s->diff_start + s->diff_height > cur_blk_height) {
397 av_log(avctx, AV_LOG_ERROR,
398 "Block parameters invalid: %d + %d > %d\n",
399 s->diff_start, s->diff_height, cur_blk_height);
400 return AVERROR_INVALIDDATA;
402 av_log(avctx, AV_LOG_DEBUG,
403 "%dx%d diff start %d height %d\n",
404 i, j, s->diff_start, s->diff_height);
408 if (s->zlibprime_prev)
409 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
411 if (s->zlibprime_curr) {
412 int col = get_bits(&gb, 8);
413 int row = get_bits(&gb, 8);
414 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n",
417 avpriv_request_sample(avctx, "zlibprime_curr");
418 return AVERROR_PATCHWELCOME;
420 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
421 av_log(avctx, AV_LOG_ERROR,
422 "no data available for zlib priming\n");
423 return AVERROR_INVALIDDATA;
425 size--; // account for flags byte
430 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
432 for (k = 0; k < cur_blk_height; k++) {
433 int x = off - k * s->frame.linesize[0] + x_pos * 3;
434 memcpy(s->frame.data[0] + x, s->keyframe + x,
439 /* skip unchanged blocks, which have size 0 */
441 if (flashsv_decode_block(avctx, avpkt, &gb, size,
442 cur_blk_width, cur_blk_height,
444 i + j * (h_blocks + !!h_part)))
445 av_log(avctx, AV_LOG_ERROR,
446 "error in decompression of block %dx%d\n", i, j);
450 if (s->is_keyframe && s->ver == 2) {
452 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
454 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
455 return AVERROR(ENOMEM);
458 memcpy(s->keyframe, s->frame.data[0],
459 s->frame.linesize[0] * avctx->height);
462 if ((ret = av_frame_ref(data, &s->frame)) < 0)
467 if ((get_bits_count(&gb) / 8) != buf_size)
468 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
469 buf_size, (get_bits_count(&gb) / 8));
471 /* report that the buffer was completely consumed */
475 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
477 FlashSVContext *s = avctx->priv_data;
478 inflateEnd(&s->zstream);
479 /* release the frame if needed */
480 av_frame_unref(&s->frame);
482 /* free the tmpblock */
483 av_free(s->tmpblock);
488 #if CONFIG_FLASHSV_DECODER
489 AVCodec ff_flashsv_decoder = {
491 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
492 .type = AVMEDIA_TYPE_VIDEO,
493 .id = AV_CODEC_ID_FLASHSV,
494 .priv_data_size = sizeof(FlashSVContext),
495 .init = flashsv_decode_init,
496 .close = flashsv_decode_end,
497 .decode = flashsv_decode_frame,
498 .capabilities = CODEC_CAP_DR1,
499 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
501 #endif /* CONFIG_FLASHSV_DECODER */
503 #if CONFIG_FLASHSV2_DECODER
504 static const uint32_t ff_flashsv2_default_palette[128] = {
505 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
506 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
507 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
508 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
509 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
510 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
511 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
512 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
513 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
514 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
515 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
516 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
517 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
518 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
519 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
520 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
521 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
522 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
523 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
524 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
525 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
529 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
531 FlashSVContext *s = avctx->priv_data;
532 flashsv_decode_init(avctx);
533 s->pal = ff_flashsv2_default_palette;
539 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
541 FlashSVContext *s = avctx->priv_data;
543 av_freep(&s->keyframedata);
544 av_freep(&s->blocks);
545 av_freep(&s->keyframe);
546 av_freep(&s->deflate_block);
547 flashsv_decode_end(avctx);
552 AVCodec ff_flashsv2_decoder = {
554 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
555 .type = AVMEDIA_TYPE_VIDEO,
556 .id = AV_CODEC_ID_FLASHSV2,
557 .priv_data_size = sizeof(FlashSVContext),
558 .init = flashsv2_decode_init,
559 .close = flashsv2_decode_end,
560 .decode = flashsv_decode_frame,
561 .capabilities = CODEC_CAP_DR1,
562 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
564 #endif /* CONFIG_FLASHSV2_DECODER */