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, const uint8_t *sptr_end, 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++) {
82 return AVERROR_INVALIDDATA;
85 unsigned c = AV_RB16(sptr) & ~0x8000;
86 unsigned b = c & 0x1F;
87 unsigned g = (c >> 5) & 0x1F;
89 /* 000aaabb -> aaabbaaa */
90 *dst++ = (b << 3) | (b >> 2);
91 *dst++ = (g << 3) | (g >> 2);
92 *dst++ = (r << 3) | (r >> 2);
96 uint32_t c = pal[*sptr++];
97 bytestream_put_le24(&dst, c);
101 return sptr - orig_src;
104 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
106 FlashSVContext *s = avctx->priv_data;
107 inflateEnd(&s->zstream);
108 /* release the frame if needed */
109 av_frame_free(&s->frame);
111 /* free the tmpblock */
112 av_freep(&s->tmpblock);
117 static av_cold int flashsv_decode_init(AVCodecContext *avctx)
119 FlashSVContext *s = avctx->priv_data;
120 int zret; // Zlib return code
123 s->zstream.zalloc = Z_NULL;
124 s->zstream.zfree = Z_NULL;
125 s->zstream.opaque = Z_NULL;
126 zret = inflateInit(&s->zstream);
128 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
131 avctx->pix_fmt = AV_PIX_FMT_BGR24;
133 s->frame = av_frame_alloc();
135 return AVERROR(ENOMEM);
141 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
144 int zret; // Zlib return code
147 return AVERROR_INVALIDDATA;
153 s->zstream.next_in = src;
154 s->zstream.avail_in = size;
155 s->zstream.next_out = s->tmpblock;
156 s->zstream.avail_out = s->block_size * 3;
157 inflate(&s->zstream, Z_SYNC_FLUSH);
159 if (deflateInit(&zs, 0) != Z_OK)
161 zs.next_in = s->tmpblock;
162 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
163 zs.next_out = s->deflate_block;
164 zs.avail_out = s->deflate_block_size;
165 deflate(&zs, Z_SYNC_FLUSH);
168 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
169 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
170 return AVERROR_UNKNOWN;
173 s->zstream.next_in = s->deflate_block;
174 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
175 s->zstream.next_out = s->tmpblock;
176 s->zstream.avail_out = s->block_size * 3;
177 inflate(&s->zstream, Z_SYNC_FLUSH);
182 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
183 GetBitContext *gb, int block_size,
184 int width, int height, int x_pos, int y_pos,
187 struct FlashSVContext *s = avctx->priv_data;
188 uint8_t *line = s->tmpblock;
190 int ret = inflateReset(&s->zstream);
192 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
193 return AVERROR_UNKNOWN;
195 if (s->zlibprime_curr || s->zlibprime_prev) {
196 ret = flashsv2_prime(s,
197 s->blocks[blk_idx].pos,
198 s->blocks[blk_idx].size);
202 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
203 s->zstream.avail_in = block_size;
204 s->zstream.next_out = s->tmpblock;
205 s->zstream.avail_out = s->block_size * 3;
206 ret = inflate(&s->zstream, Z_FINISH);
207 if (ret == Z_DATA_ERROR) {
208 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
209 inflateSync(&s->zstream);
210 ret = inflate(&s->zstream, Z_FINISH);
213 if (ret != Z_OK && ret != Z_STREAM_END) {
217 if (s->is_keyframe) {
218 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
219 s->blocks[blk_idx].size = block_size;
222 y_pos += s->diff_start;
224 if (!s->color_depth) {
225 /* Flash Screen Video stores the image upside down, so copy
226 * lines to destination in reverse order. */
227 for (k = 1; k <= s->diff_height; k++) {
228 memcpy(s->frame->data[0] + x_pos * 3 +
229 (s->image_height - y_pos - k) * s->frame->linesize[0],
231 /* advance source pointer to next line */
235 /* hybrid 15-bit/palette mode */
236 ret = decode_hybrid(s->tmpblock, s->zstream.next_out,
238 s->image_height - (y_pos + 1 + s->diff_height),
239 x_pos, s->diff_height, width,
240 s->frame->linesize[0], s->pal);
242 av_log(avctx, AV_LOG_ERROR, "decode_hybrid failed\n");
246 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
250 static int calc_deflate_block_size(int tmpblock_size)
255 zstream.zalloc = Z_NULL;
256 zstream.zfree = Z_NULL;
257 zstream.opaque = Z_NULL;
258 if (deflateInit(&zstream, 0) != Z_OK)
260 size = deflateBound(&zstream, tmpblock_size);
261 deflateEnd(&zstream);
266 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
267 int *got_frame, AVPacket *avpkt)
269 int buf_size = avpkt->size;
270 FlashSVContext *s = avctx->priv_data;
271 int h_blocks, v_blocks, h_part, v_part, i, j, ret;
273 int last_blockwidth = s->block_width;
274 int last_blockheight= s->block_height;
276 /* no supplementary picture */
282 if ((ret = init_get_bits8(&gb, avpkt->data, buf_size)) < 0)
285 /* start to parse the bitstream */
286 s->block_width = 16 * (get_bits(&gb, 4) + 1);
287 s->image_width = get_bits(&gb, 12);
288 s->block_height = 16 * (get_bits(&gb, 4) + 1);
289 s->image_height = get_bits(&gb, 12);
291 if ( last_blockwidth != s->block_width
292 || last_blockheight!= s->block_height)
293 av_freep(&s->blocks);
297 if (get_bits1(&gb)) {
298 avpriv_request_sample(avctx, "iframe");
299 return AVERROR_PATCHWELCOME;
301 if (get_bits1(&gb)) {
302 avpriv_request_sample(avctx, "Custom palette");
303 return AVERROR_PATCHWELCOME;
307 /* calculate number of blocks and size of border (partial) blocks */
308 h_blocks = s->image_width / s->block_width;
309 h_part = s->image_width % s->block_width;
310 v_blocks = s->image_height / s->block_height;
311 v_part = s->image_height % s->block_height;
313 /* the block size could change between frames, make sure the buffer
314 * is large enough, if not, get a larger one */
315 if (s->block_size < s->block_width * s->block_height) {
316 int tmpblock_size = 3 * s->block_width * s->block_height, err;
318 if ((err = av_reallocp(&s->tmpblock, tmpblock_size)) < 0) {
320 av_log(avctx, AV_LOG_ERROR,
321 "Cannot allocate decompression buffer.\n");
325 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
326 if (s->deflate_block_size <= 0) {
327 av_log(avctx, AV_LOG_ERROR,
328 "Cannot determine deflate buffer size.\n");
331 if ((err = av_reallocp(&s->deflate_block, s->deflate_block_size)) < 0) {
333 av_log(avctx, AV_LOG_ERROR, "Cannot allocate deflate buffer.\n");
338 s->block_size = s->block_width * s->block_height;
340 /* initialize the image size once */
341 if (avctx->width == 0 && avctx->height == 0) {
342 if ((ret = ff_set_dimensions(avctx, s->image_width, s->image_height)) < 0)
346 /* check for changes of image width and image height */
347 if (avctx->width != s->image_width || avctx->height != s->image_height) {
348 av_log(avctx, AV_LOG_ERROR,
349 "Frame width or height differs from first frame!\n");
350 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
351 avctx->height, avctx->width, s->image_height, s->image_width);
352 return AVERROR_INVALIDDATA;
355 /* we care for keyframes only in Screen Video v2 */
356 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
357 if (s->is_keyframe) {
359 if ((err = av_reallocp(&s->keyframedata, avpkt->size)) < 0)
361 memcpy(s->keyframedata, avpkt->data, avpkt->size);
363 if(s->ver == 2 && !s->blocks)
364 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part) *
365 sizeof(s->blocks[0]));
367 ff_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
368 s->image_width, s->image_height, s->block_width, s->block_height,
369 h_blocks, v_blocks, h_part, v_part);
371 if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
374 /* loop over all block columns */
375 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
377 int y_pos = j * s->block_height; // vertical position in frame
378 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
380 /* loop over all block rows */
381 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
382 int x_pos = i * s->block_width; // horizontal position in frame
383 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
386 /* get the size of the compressed zlib chunk */
387 int size = get_bits(&gb, 16);
390 s->zlibprime_curr = 0;
391 s->zlibprime_prev = 0;
393 s->diff_height = cur_blk_height;
395 if (8 * size > get_bits_left(&gb)) {
396 av_frame_unref(s->frame);
397 return AVERROR_INVALIDDATA;
400 if (s->ver == 2 && size) {
402 s->color_depth = get_bits(&gb, 2);
403 has_diff = get_bits1(&gb);
404 s->zlibprime_curr = get_bits1(&gb);
405 s->zlibprime_prev = get_bits1(&gb);
407 if (s->color_depth != 0 && s->color_depth != 2) {
408 av_log(avctx, AV_LOG_ERROR,
409 "%dx%d invalid color depth %d\n",
410 i, j, s->color_depth);
411 return AVERROR_INVALIDDATA;
416 av_log(avctx, AV_LOG_ERROR, "size too small for diff\n");
417 return AVERROR_INVALIDDATA;
420 av_log(avctx, AV_LOG_ERROR,
421 "Inter frame without keyframe\n");
422 return AVERROR_INVALIDDATA;
424 s->diff_start = get_bits(&gb, 8);
425 s->diff_height = get_bits(&gb, 8);
426 if (s->diff_start + s->diff_height > cur_blk_height) {
427 av_log(avctx, AV_LOG_ERROR,
428 "Block parameters invalid: %d + %d > %d\n",
429 s->diff_start, s->diff_height, cur_blk_height);
430 return AVERROR_INVALIDDATA;
432 av_log(avctx, AV_LOG_DEBUG,
433 "%dx%d diff start %d height %d\n",
434 i, j, s->diff_start, s->diff_height);
438 if (s->zlibprime_prev)
439 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
441 if (s->zlibprime_curr) {
442 int col = get_bits(&gb, 8);
443 int row = get_bits(&gb, 8);
444 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n",
447 av_log(avctx, AV_LOG_ERROR, "size too small for zlibprime_curr\n");
448 return AVERROR_INVALIDDATA;
451 avpriv_request_sample(avctx, "zlibprime_curr");
452 return AVERROR_PATCHWELCOME;
454 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
455 av_log(avctx, AV_LOG_ERROR,
456 "no data available for zlib priming\n");
457 return AVERROR_INVALIDDATA;
459 size--; // account for flags byte
464 int off = (s->image_height - y_pos - 1) * s->frame->linesize[0];
466 for (k = 0; k < cur_blk_height; k++) {
467 int x = off - k * s->frame->linesize[0] + x_pos * 3;
468 memcpy(s->frame->data[0] + x, s->keyframe + x,
473 /* skip unchanged blocks, which have size 0 */
475 if (flashsv_decode_block(avctx, avpkt, &gb, size,
476 cur_blk_width, cur_blk_height,
478 i + j * (h_blocks + !!h_part)))
479 av_log(avctx, AV_LOG_ERROR,
480 "error in decompression of block %dx%d\n", i, j);
484 if (s->is_keyframe && s->ver == 2) {
486 s->keyframe = av_malloc(s->frame->linesize[0] * avctx->height);
488 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
489 return AVERROR(ENOMEM);
492 memcpy(s->keyframe, s->frame->data[0],
493 s->frame->linesize[0] * avctx->height);
496 if ((ret = av_frame_ref(data, s->frame)) < 0)
501 if ((get_bits_count(&gb) / 8) != buf_size)
502 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
503 buf_size, (get_bits_count(&gb) / 8));
505 /* report that the buffer was completely consumed */
509 #if CONFIG_FLASHSV_DECODER
510 AVCodec ff_flashsv_decoder = {
512 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
513 .type = AVMEDIA_TYPE_VIDEO,
514 .id = AV_CODEC_ID_FLASHSV,
515 .priv_data_size = sizeof(FlashSVContext),
516 .init = flashsv_decode_init,
517 .close = flashsv_decode_end,
518 .decode = flashsv_decode_frame,
519 .capabilities = AV_CODEC_CAP_DR1,
520 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
521 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
523 #endif /* CONFIG_FLASHSV_DECODER */
525 #if CONFIG_FLASHSV2_DECODER
526 static const uint32_t ff_flashsv2_default_palette[128] = {
527 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
528 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
529 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
530 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
531 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
532 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
533 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
534 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
535 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
536 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
537 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
538 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
539 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
540 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
541 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
542 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
543 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
544 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
545 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
546 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
547 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
551 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
553 FlashSVContext *s = avctx->priv_data;
556 ret = flashsv_decode_init(avctx);
559 s->pal = ff_flashsv2_default_palette;
565 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
567 FlashSVContext *s = avctx->priv_data;
569 av_freep(&s->keyframedata);
570 av_freep(&s->blocks);
571 av_freep(&s->keyframe);
572 av_freep(&s->deflate_block);
573 flashsv_decode_end(avctx);
578 AVCodec ff_flashsv2_decoder = {
580 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
581 .type = AVMEDIA_TYPE_VIDEO,
582 .id = AV_CODEC_ID_FLASHSV2,
583 .priv_data_size = sizeof(FlashSVContext),
584 .init = flashsv2_decode_init,
585 .close = flashsv2_decode_end,
586 .decode = flashsv_decode_frame,
587 .capabilities = AV_CODEC_CAP_DR1,
588 .caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
589 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
591 #endif /* CONFIG_FLASHSV2_DECODER */