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;
73 static int decode_hybrid(const uint8_t *sptr, uint8_t *dptr, int dx, int dy,
74 int h, int w, int stride, const uint32_t *pal)
77 const uint8_t *orig_src = sptr;
79 for (y = dx+h; y > dx; y--) {
80 uint8_t *dst = dptr + (y * stride) + dy * 3;
81 for (x = 0; x < w; x++) {
84 unsigned c = AV_RB16(sptr) & ~0x8000;
85 unsigned b = c & 0x1F;
86 unsigned g = (c >> 5) & 0x1F;
88 /* 000aaabb -> aaabbaaa */
89 *dst++ = (b << 3) | (b >> 2);
90 *dst++ = (g << 3) | (g >> 2);
91 *dst++ = (r << 3) | (r >> 2);
95 uint32_t c = pal[*sptr++];
96 bytestream_put_le24(&dst, c);
100 return sptr - orig_src;
103 static av_cold int flashsv_decode_init(AVCodecContext *avctx)
105 FlashSVContext *s = avctx->priv_data;
106 int zret; // Zlib return code
109 s->zstream.zalloc = Z_NULL;
110 s->zstream.zfree = Z_NULL;
111 s->zstream.opaque = Z_NULL;
112 zret = inflateInit(&s->zstream);
114 av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
117 avctx->pix_fmt = AV_PIX_FMT_BGR24;
118 avcodec_get_frame_defaults(&s->frame);
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, ret;
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 avpriv_request_sample(avctx, "iframe");
273 return AVERROR_PATCHWELCOME;
275 if (get_bits1(&gb)) {
276 avpriv_request_sample(avctx, "Custom palette");
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 if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
343 /* loop over all block columns */
344 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
346 int y_pos = j * s->block_height; // vertical position in frame
347 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
349 /* loop over all block rows */
350 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
351 int x_pos = i * s->block_width; // horizontal position in frame
352 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
355 /* get the size of the compressed zlib chunk */
356 int size = get_bits(&gb, 16);
359 s->zlibprime_curr = 0;
360 s->zlibprime_prev = 0;
362 s->diff_height = cur_blk_height;
364 if (8 * size > get_bits_left(&gb)) {
365 av_frame_unref(&s->frame);
366 return AVERROR_INVALIDDATA;
369 if (s->ver == 2 && size) {
371 s->color_depth = get_bits(&gb, 2);
372 has_diff = get_bits1(&gb);
373 s->zlibprime_curr = get_bits1(&gb);
374 s->zlibprime_prev = get_bits1(&gb);
376 if (s->color_depth != 0 && s->color_depth != 2) {
377 av_log(avctx, AV_LOG_ERROR,
378 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
379 return AVERROR_INVALIDDATA;
384 av_log(avctx, AV_LOG_ERROR,
385 "inter frame without keyframe\n");
386 return AVERROR_INVALIDDATA;
388 s->diff_start = get_bits(&gb, 8);
389 s->diff_height = get_bits(&gb, 8);
390 if (s->diff_start + s->diff_height > cur_blk_height) {
391 av_log(avctx, AV_LOG_ERROR, "Block parameters invalid\n");
392 return AVERROR_INVALIDDATA;
394 av_log(avctx, AV_LOG_DEBUG,
395 "%dx%d diff start %d height %d\n",
396 i, j, s->diff_start, s->diff_height);
400 if (s->zlibprime_prev)
401 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
403 if (s->zlibprime_curr) {
404 int col = get_bits(&gb, 8);
405 int row = get_bits(&gb, 8);
406 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
408 avpriv_request_sample(avctx, "zlibprime_curr");
409 return AVERROR_PATCHWELCOME;
411 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
412 av_log(avctx, AV_LOG_ERROR, "no data available for zlib "
414 return AVERROR_INVALIDDATA;
416 size--; // account for flags byte
421 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
423 for (k = 0; k < cur_blk_height; k++)
424 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
425 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
429 /* skip unchanged blocks, which have size 0 */
431 if (flashsv_decode_block(avctx, avpkt, &gb, size,
432 cur_blk_width, cur_blk_height,
434 i + j * (h_blocks + !!h_part)))
435 av_log(avctx, AV_LOG_ERROR,
436 "error in decompression of block %dx%d\n", i, j);
440 if (s->is_keyframe && s->ver == 2) {
442 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
444 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
445 return AVERROR(ENOMEM);
448 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
451 if ((ret = av_frame_ref(data, &s->frame)) < 0)
456 if ((get_bits_count(&gb) / 8) != buf_size)
457 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
458 buf_size, (get_bits_count(&gb) / 8));
460 /* report that the buffer was completely consumed */
465 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
467 FlashSVContext *s = avctx->priv_data;
468 inflateEnd(&s->zstream);
469 /* release the frame if needed */
470 av_frame_unref(&s->frame);
472 /* free the tmpblock */
473 av_free(s->tmpblock);
479 #if CONFIG_FLASHSV_DECODER
480 AVCodec ff_flashsv_decoder = {
482 .type = AVMEDIA_TYPE_VIDEO,
483 .id = AV_CODEC_ID_FLASHSV,
484 .priv_data_size = sizeof(FlashSVContext),
485 .init = flashsv_decode_init,
486 .close = flashsv_decode_end,
487 .decode = flashsv_decode_frame,
488 .capabilities = CODEC_CAP_DR1,
489 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
490 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
492 #endif /* CONFIG_FLASHSV_DECODER */
494 #if CONFIG_FLASHSV2_DECODER
495 static const uint32_t ff_flashsv2_default_palette[128] = {
496 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
497 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
498 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
499 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
500 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
501 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
502 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
503 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
504 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
505 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
506 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
507 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
508 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
509 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
510 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
511 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
512 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
513 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
514 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
515 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
516 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
520 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
522 FlashSVContext *s = avctx->priv_data;
523 flashsv_decode_init(avctx);
524 s->pal = ff_flashsv2_default_palette;
530 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
532 FlashSVContext *s = avctx->priv_data;
534 av_freep(&s->keyframedata);
535 av_freep(&s->blocks);
536 av_freep(&s->keyframe);
537 av_freep(&s->deflate_block);
538 flashsv_decode_end(avctx);
543 AVCodec ff_flashsv2_decoder = {
545 .type = AVMEDIA_TYPE_VIDEO,
546 .id = AV_CODEC_ID_FLASHSV2,
547 .priv_data_size = sizeof(FlashSVContext),
548 .init = flashsv2_decode_init,
549 .close = flashsv2_decode_end,
550 .decode = flashsv_decode_frame,
551 .capabilities = CODEC_CAP_DR1,
552 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
553 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
555 #endif /* CONFIG_FLASHSV2_DECODER */