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;
205 y_pos += s->diff_start;
207 if (!s->color_depth) {
208 /* Flash Screen Video stores the image upside down, so copy
209 * lines to destination in reverse order. */
210 for (k = 1; k <= s->diff_height; k++) {
211 memcpy(s->frame.data[0] + x_pos * 3 +
212 (s->image_height - y_pos - k) * s->frame.linesize[0],
214 /* advance source pointer to next line */
218 /* hybrid 15-bit/palette mode */
219 decode_hybrid(s->tmpblock, s->frame.data[0],
220 s->image_height - (y_pos + 1 + s->diff_height),
221 x_pos, s->diff_height, width,
222 s->frame.linesize[0], s->pal);
224 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
228 static int calc_deflate_block_size(int tmpblock_size)
233 zstream.zalloc = Z_NULL;
234 zstream.zfree = Z_NULL;
235 zstream.opaque = Z_NULL;
236 if (deflateInit(&zstream, 0) != Z_OK)
238 size = deflateBound(&zstream, tmpblock_size);
239 deflateEnd(&zstream);
244 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
245 int *got_frame, AVPacket *avpkt)
247 int buf_size = avpkt->size;
248 FlashSVContext *s = avctx->priv_data;
249 int h_blocks, v_blocks, h_part, v_part, i, j, ret;
251 int last_blockwidth = s->block_width;
252 int last_blockheight= s->block_height;
254 /* no supplementary picture */
260 init_get_bits(&gb, avpkt->data, buf_size * 8);
262 /* start to parse the bitstream */
263 s->block_width = 16 * (get_bits(&gb, 4) + 1);
264 s->image_width = get_bits(&gb, 12);
265 s->block_height = 16 * (get_bits(&gb, 4) + 1);
266 s->image_height = get_bits(&gb, 12);
268 if ( last_blockwidth != s->block_width
269 || last_blockheight!= s->block_height)
270 av_freep(&s->blocks);
274 if (get_bits1(&gb)) {
275 avpriv_request_sample(avctx, "iframe");
276 return AVERROR_PATCHWELCOME;
278 if (get_bits1(&gb)) {
279 avpriv_request_sample(avctx, "Custom palette");
280 return AVERROR_PATCHWELCOME;
284 /* calculate number of blocks and size of border (partial) blocks */
285 h_blocks = s->image_width / s->block_width;
286 h_part = s->image_width % s->block_width;
287 v_blocks = s->image_height / s->block_height;
288 v_part = s->image_height % s->block_height;
290 /* the block size could change between frames, make sure the buffer
291 * is large enough, if not, get a larger one */
292 if (s->block_size < s->block_width * s->block_height) {
293 int tmpblock_size = 3 * s->block_width * s->block_height;
295 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
297 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
298 return AVERROR(ENOMEM);
301 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
302 if (s->deflate_block_size <= 0) {
303 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
306 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
307 if (!s->deflate_block) {
308 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
309 return AVERROR(ENOMEM);
313 s->block_size = s->block_width * s->block_height;
315 /* initialize the image size once */
316 if (avctx->width == 0 && avctx->height == 0) {
317 avcodec_set_dimensions(avctx, s->image_width, s->image_height);
320 /* check for changes of image width and image height */
321 if (avctx->width != s->image_width || avctx->height != s->image_height) {
322 av_log(avctx, AV_LOG_ERROR,
323 "Frame width or height differs from first frame!\n");
324 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
325 avctx->height, avctx->width, s->image_height, s->image_width);
326 return AVERROR_INVALIDDATA;
329 /* we care for keyframes only in Screen Video v2 */
330 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
331 if (s->is_keyframe) {
332 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
333 memcpy(s->keyframedata, avpkt->data, avpkt->size);
335 if(s->ver == 2 && !s->blocks)
336 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part)
337 * sizeof(s->blocks[0]));
339 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
340 s->image_width, s->image_height, s->block_width, s->block_height,
341 h_blocks, v_blocks, h_part, v_part);
343 if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
346 /* loop over all block columns */
347 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
349 int y_pos = j * s->block_height; // vertical position in frame
350 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
352 /* loop over all block rows */
353 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
354 int x_pos = i * s->block_width; // horizontal position in frame
355 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
358 /* get the size of the compressed zlib chunk */
359 int size = get_bits(&gb, 16);
362 s->zlibprime_curr = 0;
363 s->zlibprime_prev = 0;
365 s->diff_height = cur_blk_height;
367 if (8 * size > get_bits_left(&gb)) {
368 av_frame_unref(&s->frame);
369 return AVERROR_INVALIDDATA;
372 if (s->ver == 2 && size) {
374 s->color_depth = get_bits(&gb, 2);
375 has_diff = get_bits1(&gb);
376 s->zlibprime_curr = get_bits1(&gb);
377 s->zlibprime_prev = get_bits1(&gb);
379 if (s->color_depth != 0 && s->color_depth != 2) {
380 av_log(avctx, AV_LOG_ERROR,
381 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
382 return AVERROR_INVALIDDATA;
387 av_log(avctx, AV_LOG_ERROR,
388 "inter frame without keyframe\n");
389 return AVERROR_INVALIDDATA;
391 s->diff_start = get_bits(&gb, 8);
392 s->diff_height = get_bits(&gb, 8);
393 if (s->diff_start + s->diff_height > cur_blk_height) {
394 av_log(avctx, AV_LOG_ERROR,
395 "Block parameters invalid: %d + %d > %d\n",
396 s->diff_start, s->diff_height, cur_blk_height);
397 return AVERROR_INVALIDDATA;
399 av_log(avctx, AV_LOG_DEBUG,
400 "%dx%d diff start %d height %d\n",
401 i, j, s->diff_start, s->diff_height);
405 if (s->zlibprime_prev)
406 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
408 if (s->zlibprime_curr) {
409 int col = get_bits(&gb, 8);
410 int row = get_bits(&gb, 8);
411 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
413 avpriv_request_sample(avctx, "zlibprime_curr");
414 return AVERROR_PATCHWELCOME;
416 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
417 av_log(avctx, AV_LOG_ERROR, "no data available for zlib "
419 return AVERROR_INVALIDDATA;
421 size--; // account for flags byte
426 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
428 for (k = 0; k < cur_blk_height; k++) {
429 int x = off - k * s->frame.linesize[0] + x_pos * 3;
430 memcpy(s->frame.data[0] + x, s->keyframe + x,
435 /* skip unchanged blocks, which have size 0 */
437 if (flashsv_decode_block(avctx, avpkt, &gb, size,
438 cur_blk_width, cur_blk_height,
440 i + j * (h_blocks + !!h_part)))
441 av_log(avctx, AV_LOG_ERROR,
442 "error in decompression of block %dx%d\n", i, j);
446 if (s->is_keyframe && s->ver == 2) {
448 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
450 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
451 return AVERROR(ENOMEM);
454 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
457 if ((ret = av_frame_ref(data, &s->frame)) < 0)
462 if ((get_bits_count(&gb) / 8) != buf_size)
463 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
464 buf_size, (get_bits_count(&gb) / 8));
466 /* report that the buffer was completely consumed */
471 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
473 FlashSVContext *s = avctx->priv_data;
474 inflateEnd(&s->zstream);
475 /* release the frame if needed */
476 av_frame_unref(&s->frame);
478 /* free the tmpblock */
479 av_free(s->tmpblock);
485 #if CONFIG_FLASHSV_DECODER
486 AVCodec ff_flashsv_decoder = {
488 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
489 .type = AVMEDIA_TYPE_VIDEO,
490 .id = AV_CODEC_ID_FLASHSV,
491 .priv_data_size = sizeof(FlashSVContext),
492 .init = flashsv_decode_init,
493 .close = flashsv_decode_end,
494 .decode = flashsv_decode_frame,
495 .capabilities = CODEC_CAP_DR1,
496 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
498 #endif /* CONFIG_FLASHSV_DECODER */
500 #if CONFIG_FLASHSV2_DECODER
501 static const uint32_t ff_flashsv2_default_palette[128] = {
502 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
503 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
504 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
505 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
506 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
507 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
508 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
509 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
510 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
511 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
512 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
513 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
514 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
515 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
516 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
517 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
518 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
519 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
520 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
521 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
522 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
526 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
528 FlashSVContext *s = avctx->priv_data;
529 flashsv_decode_init(avctx);
530 s->pal = ff_flashsv2_default_palette;
536 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
538 FlashSVContext *s = avctx->priv_data;
540 av_freep(&s->keyframedata);
541 av_freep(&s->blocks);
542 av_freep(&s->keyframe);
543 av_freep(&s->deflate_block);
544 flashsv_decode_end(avctx);
549 AVCodec ff_flashsv2_decoder = {
551 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
552 .type = AVMEDIA_TYPE_VIDEO,
553 .id = AV_CODEC_ID_FLASHSV2,
554 .priv_data_size = sizeof(FlashSVContext),
555 .init = flashsv2_decode_init,
556 .close = flashsv2_decode_end,
557 .decode = flashsv_decode_frame,
558 .capabilities = CODEC_CAP_DR1,
559 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
561 #endif /* CONFIG_FLASHSV2_DECODER */