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
130 return AVERROR_INVALIDDATA;
136 s->zstream.next_in = src;
137 s->zstream.avail_in = size;
138 s->zstream.next_out = s->tmpblock;
139 s->zstream.avail_out = s->block_size * 3;
140 inflate(&s->zstream, Z_SYNC_FLUSH);
142 if (deflateInit(&zs, 0) != Z_OK)
144 zs.next_in = s->tmpblock;
145 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
146 zs.next_out = s->deflate_block;
147 zs.avail_out = s->deflate_block_size;
148 deflate(&zs, Z_SYNC_FLUSH);
151 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
152 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
153 return AVERROR_UNKNOWN;
156 s->zstream.next_in = s->deflate_block;
157 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
158 s->zstream.next_out = s->tmpblock;
159 s->zstream.avail_out = s->block_size * 3;
160 inflate(&s->zstream, Z_SYNC_FLUSH);
165 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
166 GetBitContext *gb, int block_size,
167 int width, int height, int x_pos, int y_pos,
170 struct FlashSVContext *s = avctx->priv_data;
171 uint8_t *line = s->tmpblock;
173 int ret = inflateReset(&s->zstream);
175 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
176 return AVERROR_UNKNOWN;
178 if (s->zlibprime_curr || s->zlibprime_prev) {
179 ret = flashsv2_prime(s,
180 s->blocks[blk_idx].pos,
181 s->blocks[blk_idx].size);
185 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
186 s->zstream.avail_in = block_size;
187 s->zstream.next_out = s->tmpblock;
188 s->zstream.avail_out = s->block_size * 3;
189 ret = inflate(&s->zstream, Z_FINISH);
190 if (ret == Z_DATA_ERROR) {
191 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
192 inflateSync(&s->zstream);
193 ret = inflate(&s->zstream, Z_FINISH);
196 if (ret != Z_OK && ret != Z_STREAM_END) {
200 if (s->is_keyframe) {
201 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
202 s->blocks[blk_idx].size = block_size;
204 if (!s->color_depth) {
205 /* Flash Screen Video stores the image upside down, so copy
206 * lines to destination in reverse order. */
207 for (k = 1; k <= s->diff_height; k++) {
208 memcpy(s->frame.data[0] + x_pos * 3 +
209 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
211 /* advance source pointer to next line */
215 /* hybrid 15-bit/palette mode */
216 decode_hybrid(s->tmpblock, s->frame.data[0],
217 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
218 x_pos, s->diff_height, width,
219 s->frame.linesize[0], s->pal);
221 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
225 static int calc_deflate_block_size(int tmpblock_size)
230 zstream.zalloc = Z_NULL;
231 zstream.zfree = Z_NULL;
232 zstream.opaque = Z_NULL;
233 if (deflateInit(&zstream, 0) != Z_OK)
235 size = deflateBound(&zstream, tmpblock_size);
236 deflateEnd(&zstream);
241 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
242 int *got_frame, AVPacket *avpkt)
244 int buf_size = avpkt->size;
245 FlashSVContext *s = avctx->priv_data;
246 int h_blocks, v_blocks, h_part, v_part, i, j;
248 int last_blockwidth = s->block_width;
249 int last_blockheight= s->block_height;
251 /* no supplementary picture */
257 init_get_bits(&gb, avpkt->data, buf_size * 8);
259 /* start to parse the bitstream */
260 s->block_width = 16 * (get_bits(&gb, 4) + 1);
261 s->image_width = get_bits(&gb, 12);
262 s->block_height = 16 * (get_bits(&gb, 4) + 1);
263 s->image_height = get_bits(&gb, 12);
265 if ( last_blockwidth != s->block_width
266 || last_blockheight!= s->block_height)
267 av_freep(&s->blocks);
271 if (get_bits1(&gb)) {
272 av_log_missing_feature(avctx, "iframe", 1);
273 return AVERROR_PATCHWELCOME;
275 if (get_bits1(&gb)) {
276 av_log_missing_feature(avctx, "Custom palette", 1);
277 return AVERROR_PATCHWELCOME;
281 /* calculate number of blocks and size of border (partial) blocks */
282 h_blocks = s->image_width / s->block_width;
283 h_part = s->image_width % s->block_width;
284 v_blocks = s->image_height / s->block_height;
285 v_part = s->image_height % s->block_height;
287 /* the block size could change between frames, make sure the buffer
288 * is large enough, if not, get a larger one */
289 if (s->block_size < s->block_width * s->block_height) {
290 int tmpblock_size = 3 * s->block_width * s->block_height;
292 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
294 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
295 return AVERROR(ENOMEM);
298 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
299 if (s->deflate_block_size <= 0) {
300 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
303 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
304 if (!s->deflate_block) {
305 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
306 return AVERROR(ENOMEM);
310 s->block_size = s->block_width * s->block_height;
312 /* initialize the image size once */
313 if (avctx->width == 0 && avctx->height == 0) {
314 avcodec_set_dimensions(avctx, s->image_width, s->image_height);
317 /* check for changes of image width and image height */
318 if (avctx->width != s->image_width || avctx->height != s->image_height) {
319 av_log(avctx, AV_LOG_ERROR,
320 "Frame width or height differs from first frame!\n");
321 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
322 avctx->height, avctx->width, s->image_height, s->image_width);
323 return AVERROR_INVALIDDATA;
326 /* we care for keyframes only in Screen Video v2 */
327 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
328 if (s->is_keyframe) {
329 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
330 memcpy(s->keyframedata, avpkt->data, avpkt->size);
332 if(s->ver == 2 && !s->blocks)
333 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part)
334 * sizeof(s->blocks[0]));
336 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
337 s->image_width, s->image_height, s->block_width, s->block_height,
338 h_blocks, v_blocks, h_part, v_part);
340 s->frame.reference = 3;
341 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
342 FF_BUFFER_HINTS_PRESERVE |
343 FF_BUFFER_HINTS_REUSABLE;
344 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
345 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
349 /* loop over all block columns */
350 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
352 int y_pos = j * s->block_height; // vertical position in frame
353 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
355 /* loop over all block rows */
356 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
357 int x_pos = i * s->block_width; // horizontal position in frame
358 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
361 /* get the size of the compressed zlib chunk */
362 int size = get_bits(&gb, 16);
365 s->zlibprime_curr = 0;
366 s->zlibprime_prev = 0;
368 s->diff_height = cur_blk_height;
370 if (8 * size > get_bits_left(&gb)) {
371 avctx->release_buffer(avctx, &s->frame);
372 s->frame.data[0] = NULL;
373 return AVERROR_INVALIDDATA;
376 if (s->ver == 2 && size) {
378 s->color_depth = get_bits(&gb, 2);
379 has_diff = get_bits1(&gb);
380 s->zlibprime_curr = get_bits1(&gb);
381 s->zlibprime_prev = get_bits1(&gb);
383 if (s->color_depth != 0 && s->color_depth != 2) {
384 av_log(avctx, AV_LOG_ERROR,
385 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
386 return AVERROR_INVALIDDATA;
391 av_log(avctx, AV_LOG_ERROR,
392 "inter frame without keyframe\n");
393 return AVERROR_INVALIDDATA;
395 s->diff_start = get_bits(&gb, 8);
396 s->diff_height = get_bits(&gb, 8);
397 av_log(avctx, AV_LOG_DEBUG,
398 "%dx%d diff start %d height %d\n",
399 i, j, s->diff_start, s->diff_height);
403 if (s->zlibprime_prev)
404 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
406 if (s->zlibprime_curr) {
407 int col = get_bits(&gb, 8);
408 int row = get_bits(&gb, 8);
409 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
411 av_log_missing_feature(avctx, "zlibprime_curr", 1);
412 return AVERROR_PATCHWELCOME;
414 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
415 av_log(avctx, AV_LOG_ERROR, "no data available for zlib "
417 return AVERROR_INVALIDDATA;
419 size--; // account for flags byte
424 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
426 for (k = 0; k < cur_blk_height; k++)
427 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
428 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
432 /* skip unchanged blocks, which have size 0 */
434 if (flashsv_decode_block(avctx, avpkt, &gb, size,
435 cur_blk_width, cur_blk_height,
437 i + j * (h_blocks + !!h_part)))
438 av_log(avctx, AV_LOG_ERROR,
439 "error in decompression of block %dx%d\n", i, j);
443 if (s->is_keyframe && s->ver == 2) {
445 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
447 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
448 return AVERROR(ENOMEM);
451 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
455 *(AVFrame*)data = s->frame;
457 if ((get_bits_count(&gb) / 8) != buf_size)
458 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
459 buf_size, (get_bits_count(&gb) / 8));
461 /* report that the buffer was completely consumed */
466 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
468 FlashSVContext *s = avctx->priv_data;
469 inflateEnd(&s->zstream);
470 /* release the frame if needed */
471 if (s->frame.data[0])
472 avctx->release_buffer(avctx, &s->frame);
474 /* free the tmpblock */
475 av_free(s->tmpblock);
481 #if CONFIG_FLASHSV_DECODER
482 AVCodec ff_flashsv_decoder = {
484 .type = AVMEDIA_TYPE_VIDEO,
485 .id = AV_CODEC_ID_FLASHSV,
486 .priv_data_size = sizeof(FlashSVContext),
487 .init = flashsv_decode_init,
488 .close = flashsv_decode_end,
489 .decode = flashsv_decode_frame,
490 .capabilities = CODEC_CAP_DR1,
491 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
492 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
494 #endif /* CONFIG_FLASHSV_DECODER */
496 #if CONFIG_FLASHSV2_DECODER
497 static const uint32_t ff_flashsv2_default_palette[128] = {
498 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
499 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
500 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
501 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
502 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
503 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
504 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
505 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
506 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
507 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
508 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
509 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
510 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
511 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
512 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
513 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
514 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
515 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
516 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
517 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
518 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
522 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
524 FlashSVContext *s = avctx->priv_data;
525 flashsv_decode_init(avctx);
526 s->pal = ff_flashsv2_default_palette;
532 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
534 FlashSVContext *s = avctx->priv_data;
536 av_freep(&s->keyframedata);
537 av_freep(&s->blocks);
538 av_freep(&s->keyframe);
539 av_freep(&s->deflate_block);
540 flashsv_decode_end(avctx);
545 AVCodec ff_flashsv2_decoder = {
547 .type = AVMEDIA_TYPE_VIDEO,
548 .id = AV_CODEC_ID_FLASHSV2,
549 .priv_data_size = sizeof(FlashSVContext),
550 .init = flashsv2_decode_init,
551 .close = flashsv2_decode_end,
552 .decode = flashsv_decode_frame,
553 .capabilities = CODEC_CAP_DR1,
554 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
555 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
557 #endif /* CONFIG_FLASHSV2_DECODER */