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 flashsv_decode_end(avctx);
136 return AVERROR(ENOMEM);
142 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
145 int zret; // Zlib return code
148 return AVERROR_INVALIDDATA;
154 s->zstream.next_in = src;
155 s->zstream.avail_in = size;
156 s->zstream.next_out = s->tmpblock;
157 s->zstream.avail_out = s->block_size * 3;
158 inflate(&s->zstream, Z_SYNC_FLUSH);
160 if (deflateInit(&zs, 0) != Z_OK)
162 zs.next_in = s->tmpblock;
163 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
164 zs.next_out = s->deflate_block;
165 zs.avail_out = s->deflate_block_size;
166 deflate(&zs, Z_SYNC_FLUSH);
169 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
170 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
171 return AVERROR_UNKNOWN;
174 s->zstream.next_in = s->deflate_block;
175 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
176 s->zstream.next_out = s->tmpblock;
177 s->zstream.avail_out = s->block_size * 3;
178 inflate(&s->zstream, Z_SYNC_FLUSH);
183 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
184 GetBitContext *gb, int block_size,
185 int width, int height, int x_pos, int y_pos,
188 struct FlashSVContext *s = avctx->priv_data;
189 uint8_t *line = s->tmpblock;
191 int ret = inflateReset(&s->zstream);
193 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
194 return AVERROR_UNKNOWN;
196 if (s->zlibprime_curr || s->zlibprime_prev) {
197 ret = flashsv2_prime(s,
198 s->blocks[blk_idx].pos,
199 s->blocks[blk_idx].size);
203 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
204 s->zstream.avail_in = block_size;
205 s->zstream.next_out = s->tmpblock;
206 s->zstream.avail_out = s->block_size * 3;
207 ret = inflate(&s->zstream, Z_FINISH);
208 if (ret == Z_DATA_ERROR) {
209 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
210 inflateSync(&s->zstream);
211 ret = inflate(&s->zstream, Z_FINISH);
214 if (ret != Z_OK && ret != Z_STREAM_END) {
218 if (s->is_keyframe) {
219 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
220 s->blocks[blk_idx].size = block_size;
223 y_pos += s->diff_start;
225 if (!s->color_depth) {
226 /* Flash Screen Video stores the image upside down, so copy
227 * lines to destination in reverse order. */
228 for (k = 1; k <= s->diff_height; k++) {
229 memcpy(s->frame->data[0] + x_pos * 3 +
230 (s->image_height - y_pos - k) * s->frame->linesize[0],
232 /* advance source pointer to next line */
236 /* hybrid 15-bit/palette mode */
237 ret = decode_hybrid(s->tmpblock, s->zstream.next_out,
239 s->image_height - (y_pos + 1 + s->diff_height),
240 x_pos, s->diff_height, width,
241 s->frame->linesize[0], s->pal);
243 av_log(avctx, AV_LOG_ERROR, "decode_hybrid failed\n");
247 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
251 static int calc_deflate_block_size(int tmpblock_size)
256 zstream.zalloc = Z_NULL;
257 zstream.zfree = Z_NULL;
258 zstream.opaque = Z_NULL;
259 if (deflateInit(&zstream, 0) != Z_OK)
261 size = deflateBound(&zstream, tmpblock_size);
262 deflateEnd(&zstream);
267 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
268 int *got_frame, AVPacket *avpkt)
270 int buf_size = avpkt->size;
271 FlashSVContext *s = avctx->priv_data;
272 int h_blocks, v_blocks, h_part, v_part, i, j, ret;
274 int last_blockwidth = s->block_width;
275 int last_blockheight= s->block_height;
277 /* no supplementary picture */
283 if ((ret = init_get_bits8(&gb, avpkt->data, buf_size)) < 0)
286 /* start to parse the bitstream */
287 s->block_width = 16 * (get_bits(&gb, 4) + 1);
288 s->image_width = get_bits(&gb, 12);
289 s->block_height = 16 * (get_bits(&gb, 4) + 1);
290 s->image_height = get_bits(&gb, 12);
292 if ( last_blockwidth != s->block_width
293 || last_blockheight!= s->block_height)
294 av_freep(&s->blocks);
298 if (get_bits1(&gb)) {
299 avpriv_request_sample(avctx, "iframe");
300 return AVERROR_PATCHWELCOME;
302 if (get_bits1(&gb)) {
303 avpriv_request_sample(avctx, "Custom palette");
304 return AVERROR_PATCHWELCOME;
308 /* calculate number of blocks and size of border (partial) blocks */
309 h_blocks = s->image_width / s->block_width;
310 h_part = s->image_width % s->block_width;
311 v_blocks = s->image_height / s->block_height;
312 v_part = s->image_height % s->block_height;
314 /* the block size could change between frames, make sure the buffer
315 * is large enough, if not, get a larger one */
316 if (s->block_size < s->block_width * s->block_height) {
317 int tmpblock_size = 3 * s->block_width * s->block_height, err;
319 if ((err = av_reallocp(&s->tmpblock, tmpblock_size)) < 0) {
321 av_log(avctx, AV_LOG_ERROR,
322 "Cannot allocate decompression buffer.\n");
326 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
327 if (s->deflate_block_size <= 0) {
328 av_log(avctx, AV_LOG_ERROR,
329 "Cannot determine deflate buffer size.\n");
332 if ((err = av_reallocp(&s->deflate_block, s->deflate_block_size)) < 0) {
334 av_log(avctx, AV_LOG_ERROR, "Cannot allocate deflate buffer.\n");
339 s->block_size = s->block_width * s->block_height;
341 /* initialize the image size once */
342 if (avctx->width == 0 && avctx->height == 0) {
343 if ((ret = ff_set_dimensions(avctx, s->image_width, s->image_height)) < 0)
347 /* check for changes of image width and image height */
348 if (avctx->width != s->image_width || avctx->height != s->image_height) {
349 av_log(avctx, AV_LOG_ERROR,
350 "Frame width or height differs from first frame!\n");
351 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
352 avctx->height, avctx->width, s->image_height, s->image_width);
353 return AVERROR_INVALIDDATA;
356 /* we care for keyframes only in Screen Video v2 */
357 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
358 if (s->is_keyframe) {
360 if ((err = av_reallocp(&s->keyframedata, avpkt->size)) < 0)
362 memcpy(s->keyframedata, avpkt->data, avpkt->size);
364 if(s->ver == 2 && !s->blocks)
365 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part) *
366 sizeof(s->blocks[0]));
368 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
369 s->image_width, s->image_height, s->block_width, s->block_height,
370 h_blocks, v_blocks, h_part, v_part);
372 if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
375 /* loop over all block columns */
376 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
378 int y_pos = j * s->block_height; // vertical position in frame
379 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
381 /* loop over all block rows */
382 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
383 int x_pos = i * s->block_width; // horizontal position in frame
384 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
387 /* get the size of the compressed zlib chunk */
388 int size = get_bits(&gb, 16);
391 s->zlibprime_curr = 0;
392 s->zlibprime_prev = 0;
394 s->diff_height = cur_blk_height;
396 if (8 * size > get_bits_left(&gb)) {
397 av_frame_unref(s->frame);
398 return AVERROR_INVALIDDATA;
401 if (s->ver == 2 && size) {
403 s->color_depth = get_bits(&gb, 2);
404 has_diff = get_bits1(&gb);
405 s->zlibprime_curr = get_bits1(&gb);
406 s->zlibprime_prev = get_bits1(&gb);
408 if (s->color_depth != 0 && s->color_depth != 2) {
409 av_log(avctx, AV_LOG_ERROR,
410 "%dx%d invalid color depth %d\n",
411 i, j, s->color_depth);
412 return AVERROR_INVALIDDATA;
417 av_log(avctx, AV_LOG_ERROR,
418 "Inter frame without keyframe\n");
419 return AVERROR_INVALIDDATA;
421 s->diff_start = get_bits(&gb, 8);
422 s->diff_height = get_bits(&gb, 8);
423 if (s->diff_start + s->diff_height > cur_blk_height) {
424 av_log(avctx, AV_LOG_ERROR,
425 "Block parameters invalid: %d + %d > %d\n",
426 s->diff_start, s->diff_height, cur_blk_height);
427 return AVERROR_INVALIDDATA;
429 av_log(avctx, AV_LOG_DEBUG,
430 "%dx%d diff start %d height %d\n",
431 i, j, s->diff_start, s->diff_height);
435 if (s->zlibprime_prev)
436 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
438 if (s->zlibprime_curr) {
439 int col = get_bits(&gb, 8);
440 int row = get_bits(&gb, 8);
441 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n",
444 avpriv_request_sample(avctx, "zlibprime_curr");
445 return AVERROR_PATCHWELCOME;
447 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
448 av_log(avctx, AV_LOG_ERROR,
449 "no data available for zlib priming\n");
450 return AVERROR_INVALIDDATA;
452 size--; // account for flags byte
457 int off = (s->image_height - y_pos - 1) * s->frame->linesize[0];
459 for (k = 0; k < cur_blk_height; k++) {
460 int x = off - k * s->frame->linesize[0] + x_pos * 3;
461 memcpy(s->frame->data[0] + x, s->keyframe + x,
466 /* skip unchanged blocks, which have size 0 */
468 if (flashsv_decode_block(avctx, avpkt, &gb, size,
469 cur_blk_width, cur_blk_height,
471 i + j * (h_blocks + !!h_part)))
472 av_log(avctx, AV_LOG_ERROR,
473 "error in decompression of block %dx%d\n", i, j);
477 if (s->is_keyframe && s->ver == 2) {
479 s->keyframe = av_malloc(s->frame->linesize[0] * avctx->height);
481 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
482 return AVERROR(ENOMEM);
485 memcpy(s->keyframe, s->frame->data[0],
486 s->frame->linesize[0] * avctx->height);
489 if ((ret = av_frame_ref(data, s->frame)) < 0)
494 if ((get_bits_count(&gb) / 8) != buf_size)
495 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
496 buf_size, (get_bits_count(&gb) / 8));
498 /* report that the buffer was completely consumed */
502 #if CONFIG_FLASHSV_DECODER
503 AVCodec ff_flashsv_decoder = {
505 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
506 .type = AVMEDIA_TYPE_VIDEO,
507 .id = AV_CODEC_ID_FLASHSV,
508 .priv_data_size = sizeof(FlashSVContext),
509 .init = flashsv_decode_init,
510 .close = flashsv_decode_end,
511 .decode = flashsv_decode_frame,
512 .capabilities = CODEC_CAP_DR1,
513 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
515 #endif /* CONFIG_FLASHSV_DECODER */
517 #if CONFIG_FLASHSV2_DECODER
518 static const uint32_t ff_flashsv2_default_palette[128] = {
519 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
520 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
521 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
522 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
523 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
524 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
525 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
526 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
527 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
528 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
529 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
530 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
531 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
532 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
533 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
534 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
535 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
536 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
537 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
538 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
539 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
543 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
545 FlashSVContext *s = avctx->priv_data;
546 flashsv_decode_init(avctx);
547 s->pal = ff_flashsv2_default_palette;
553 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
555 FlashSVContext *s = avctx->priv_data;
557 av_freep(&s->keyframedata);
558 av_freep(&s->blocks);
559 av_freep(&s->keyframe);
560 av_freep(&s->deflate_block);
561 flashsv_decode_end(avctx);
566 AVCodec ff_flashsv2_decoder = {
568 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
569 .type = AVMEDIA_TYPE_VIDEO,
570 .id = AV_CODEC_ID_FLASHSV2,
571 .priv_data_size = sizeof(FlashSVContext),
572 .init = flashsv2_decode_init,
573 .close = flashsv2_decode_end,
574 .decode = flashsv_decode_frame,
575 .capabilities = CODEC_CAP_DR1,
576 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
578 #endif /* CONFIG_FLASHSV2_DECODER */