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, 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);
122 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
125 int zret; // Zlib return code
128 return AVERROR_INVALIDDATA;
134 s->zstream.next_in = src;
135 s->zstream.avail_in = size;
136 s->zstream.next_out = s->tmpblock;
137 s->zstream.avail_out = s->block_size * 3;
138 inflate(&s->zstream, Z_SYNC_FLUSH);
140 if (deflateInit(&zs, 0) != Z_OK)
142 zs.next_in = s->tmpblock;
143 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
144 zs.next_out = s->deflate_block;
145 zs.avail_out = s->deflate_block_size;
146 deflate(&zs, Z_SYNC_FLUSH);
149 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
150 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
151 return AVERROR_UNKNOWN;
154 s->zstream.next_in = s->deflate_block;
155 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
156 s->zstream.next_out = s->tmpblock;
157 s->zstream.avail_out = s->block_size * 3;
158 inflate(&s->zstream, Z_SYNC_FLUSH);
163 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
164 GetBitContext *gb, int block_size,
165 int width, int height, int x_pos, int y_pos,
168 struct FlashSVContext *s = avctx->priv_data;
169 uint8_t *line = s->tmpblock;
171 int ret = inflateReset(&s->zstream);
173 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
174 return AVERROR_UNKNOWN;
176 if (s->zlibprime_curr || s->zlibprime_prev) {
177 ret = flashsv2_prime(s,
178 s->blocks[blk_idx].pos,
179 s->blocks[blk_idx].size);
183 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
184 s->zstream.avail_in = block_size;
185 s->zstream.next_out = s->tmpblock;
186 s->zstream.avail_out = s->block_size * 3;
187 ret = inflate(&s->zstream, Z_FINISH);
188 if (ret == Z_DATA_ERROR) {
189 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
190 inflateSync(&s->zstream);
191 ret = inflate(&s->zstream, Z_FINISH);
194 if (ret != Z_OK && ret != Z_STREAM_END) {
198 if (s->is_keyframe) {
199 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
200 s->blocks[blk_idx].size = block_size;
203 y_pos += s->diff_start;
205 if (!s->color_depth) {
206 /* Flash Screen Video stores the image upside down, so copy
207 * lines to destination in reverse order. */
208 for (k = 1; k <= s->diff_height; k++) {
209 memcpy(s->frame.data[0] + x_pos * 3 +
210 (s->image_height - y_pos - k) * s->frame.linesize[0],
212 /* advance source pointer to next line */
216 /* hybrid 15-bit/palette mode */
217 decode_hybrid(s->tmpblock, s->frame.data[0],
218 s->image_height - (y_pos + 1 + s->diff_height),
219 x_pos, s->diff_height, width,
220 s->frame.linesize[0], s->pal);
222 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
226 static int calc_deflate_block_size(int tmpblock_size)
231 zstream.zalloc = Z_NULL;
232 zstream.zfree = Z_NULL;
233 zstream.opaque = Z_NULL;
234 if (deflateInit(&zstream, 0) != Z_OK)
236 size = deflateBound(&zstream, tmpblock_size);
237 deflateEnd(&zstream);
242 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
243 int *got_frame, AVPacket *avpkt)
245 int buf_size = avpkt->size;
246 FlashSVContext *s = avctx->priv_data;
247 int h_blocks, v_blocks, h_part, v_part, i, j, ret;
249 int last_blockwidth = s->block_width;
250 int last_blockheight= s->block_height;
252 /* no supplementary picture */
258 if ((ret = init_get_bits8(&gb, avpkt->data, buf_size)) < 0)
261 /* start to parse the bitstream */
262 s->block_width = 16 * (get_bits(&gb, 4) + 1);
263 s->image_width = get_bits(&gb, 12);
264 s->block_height = 16 * (get_bits(&gb, 4) + 1);
265 s->image_height = get_bits(&gb, 12);
267 if ( last_blockwidth != s->block_width
268 || last_blockheight!= s->block_height)
269 av_freep(&s->blocks);
273 if (get_bits1(&gb)) {
274 avpriv_request_sample(avctx, "iframe");
275 return AVERROR_PATCHWELCOME;
277 if (get_bits1(&gb)) {
278 avpriv_request_sample(avctx, "Custom palette");
279 return AVERROR_PATCHWELCOME;
283 /* calculate number of blocks and size of border (partial) blocks */
284 h_blocks = s->image_width / s->block_width;
285 h_part = s->image_width % s->block_width;
286 v_blocks = s->image_height / s->block_height;
287 v_part = s->image_height % s->block_height;
289 /* the block size could change between frames, make sure the buffer
290 * is large enough, if not, get a larger one */
291 if (s->block_size < s->block_width * s->block_height) {
292 int tmpblock_size = 3 * s->block_width * s->block_height;
294 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
296 av_log(avctx, AV_LOG_ERROR,
297 "Cannot 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,
304 "Cannot determine deflate buffer size.\n");
307 s->deflate_block = av_realloc(s->deflate_block,
308 s->deflate_block_size);
309 if (!s->deflate_block) {
310 av_log(avctx, AV_LOG_ERROR,
311 "Cannot allocate deflate buffer.\n");
312 return AVERROR(ENOMEM);
316 s->block_size = s->block_width * s->block_height;
318 /* initialize the image size once */
319 if (avctx->width == 0 && avctx->height == 0) {
320 if ((ret = ff_set_dimensions(avctx, s->image_width, s->image_height)) < 0)
324 /* check for changes of image width and image height */
325 if (avctx->width != s->image_width || avctx->height != s->image_height) {
326 av_log(avctx, AV_LOG_ERROR,
327 "Frame width or height differs from first frame!\n");
328 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
329 avctx->height, avctx->width, s->image_height, s->image_width);
330 return AVERROR_INVALIDDATA;
333 /* we care for keyframes only in Screen Video v2 */
334 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
335 if (s->is_keyframe) {
336 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
337 memcpy(s->keyframedata, avpkt->data, avpkt->size);
339 if(s->ver == 2 && !s->blocks)
340 s->blocks = av_mallocz((v_blocks + !!v_part) * (h_blocks + !!h_part) *
341 sizeof(s->blocks[0]));
343 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
344 s->image_width, s->image_height, s->block_width, s->block_height,
345 h_blocks, v_blocks, h_part, v_part);
347 if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
350 /* loop over all block columns */
351 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
353 int y_pos = j * s->block_height; // vertical position in frame
354 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
356 /* loop over all block rows */
357 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
358 int x_pos = i * s->block_width; // horizontal position in frame
359 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
362 /* get the size of the compressed zlib chunk */
363 int size = get_bits(&gb, 16);
366 s->zlibprime_curr = 0;
367 s->zlibprime_prev = 0;
369 s->diff_height = cur_blk_height;
371 if (8 * size > get_bits_left(&gb)) {
372 av_frame_unref(&s->frame);
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",
386 i, j, s->color_depth);
387 return AVERROR_INVALIDDATA;
392 av_log(avctx, AV_LOG_ERROR,
393 "Inter frame without keyframe\n");
394 return AVERROR_INVALIDDATA;
396 s->diff_start = get_bits(&gb, 8);
397 s->diff_height = get_bits(&gb, 8);
398 if (s->diff_start + s->diff_height > cur_blk_height) {
399 av_log(avctx, AV_LOG_ERROR,
400 "Block parameters invalid: %d + %d > %d\n",
401 s->diff_start, s->diff_height, cur_blk_height);
402 return AVERROR_INVALIDDATA;
404 av_log(avctx, AV_LOG_DEBUG,
405 "%dx%d diff start %d height %d\n",
406 i, j, s->diff_start, s->diff_height);
410 if (s->zlibprime_prev)
411 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
413 if (s->zlibprime_curr) {
414 int col = get_bits(&gb, 8);
415 int row = get_bits(&gb, 8);
416 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n",
419 avpriv_request_sample(avctx, "zlibprime_curr");
420 return AVERROR_PATCHWELCOME;
422 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
423 av_log(avctx, AV_LOG_ERROR,
424 "no data available for zlib priming\n");
425 return AVERROR_INVALIDDATA;
427 size--; // account for flags byte
432 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
434 for (k = 0; k < cur_blk_height; k++) {
435 int x = off - k * s->frame.linesize[0] + x_pos * 3;
436 memcpy(s->frame.data[0] + x, s->keyframe + x,
441 /* skip unchanged blocks, which have size 0 */
443 if (flashsv_decode_block(avctx, avpkt, &gb, size,
444 cur_blk_width, cur_blk_height,
446 i + j * (h_blocks + !!h_part)))
447 av_log(avctx, AV_LOG_ERROR,
448 "error in decompression of block %dx%d\n", i, j);
452 if (s->is_keyframe && s->ver == 2) {
454 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
456 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
457 return AVERROR(ENOMEM);
460 memcpy(s->keyframe, s->frame.data[0],
461 s->frame.linesize[0] * avctx->height);
464 if ((ret = av_frame_ref(data, &s->frame)) < 0)
469 if ((get_bits_count(&gb) / 8) != buf_size)
470 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
471 buf_size, (get_bits_count(&gb) / 8));
473 /* report that the buffer was completely consumed */
477 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
479 FlashSVContext *s = avctx->priv_data;
480 inflateEnd(&s->zstream);
481 /* release the frame if needed */
482 av_frame_unref(&s->frame);
484 /* free the tmpblock */
485 av_freep(&s->tmpblock);
490 #if CONFIG_FLASHSV_DECODER
491 AVCodec ff_flashsv_decoder = {
493 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
494 .type = AVMEDIA_TYPE_VIDEO,
495 .id = AV_CODEC_ID_FLASHSV,
496 .priv_data_size = sizeof(FlashSVContext),
497 .init = flashsv_decode_init,
498 .close = flashsv_decode_end,
499 .decode = flashsv_decode_frame,
500 .capabilities = CODEC_CAP_DR1,
501 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
503 #endif /* CONFIG_FLASHSV_DECODER */
505 #if CONFIG_FLASHSV2_DECODER
506 static const uint32_t ff_flashsv2_default_palette[128] = {
507 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
508 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
509 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
510 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
511 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
512 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
513 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
514 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
515 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
516 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
517 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
518 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
519 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
520 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
521 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
522 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
523 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
524 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
525 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
526 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
527 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
531 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
533 FlashSVContext *s = avctx->priv_data;
534 flashsv_decode_init(avctx);
535 s->pal = ff_flashsv2_default_palette;
541 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
543 FlashSVContext *s = avctx->priv_data;
545 av_freep(&s->keyframedata);
546 av_freep(&s->blocks);
547 av_freep(&s->keyframe);
548 av_freep(&s->deflate_block);
549 flashsv_decode_end(avctx);
554 AVCodec ff_flashsv2_decoder = {
556 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
557 .type = AVMEDIA_TYPE_VIDEO,
558 .id = AV_CODEC_ID_FLASHSV2,
559 .priv_data_size = sizeof(FlashSVContext),
560 .init = flashsv2_decode_init,
561 .close = flashsv2_decode_end,
562 .decode = flashsv_decode_frame,
563 .capabilities = CODEC_CAP_DR1,
564 .pix_fmts = (const enum AVPixelFormat[]) { AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
566 #endif /* CONFIG_FLASHSV2_DECODER */