2 * Flash Screen Video decoder
3 * Copyright (C) 2004 Alex Beregszaszi
4 * Copyright (C) 2006 Benjamin Larsson
6 * This file is part of Libav.
8 * Libav 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 * Libav 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 Libav; 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
133 s->zstream.next_in = src;
134 s->zstream.avail_in = size;
135 s->zstream.next_out = s->tmpblock;
136 s->zstream.avail_out = s->block_size * 3;
137 inflate(&s->zstream, Z_SYNC_FLUSH);
140 zs.next_in = s->tmpblock;
141 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
142 zs.next_out = s->deflate_block;
143 zs.avail_out = s->deflate_block_size;
144 deflate(&zs, Z_SYNC_FLUSH);
147 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
148 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
149 return AVERROR_UNKNOWN;
152 s->zstream.next_in = s->deflate_block;
153 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
154 s->zstream.next_out = s->tmpblock;
155 s->zstream.avail_out = s->block_size * 3;
156 inflate(&s->zstream, Z_SYNC_FLUSH);
161 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
162 GetBitContext *gb, int block_size,
163 int width, int height, int x_pos, int y_pos,
166 struct FlashSVContext *s = avctx->priv_data;
167 uint8_t *line = s->tmpblock;
169 int ret = inflateReset(&s->zstream);
171 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
172 return AVERROR_UNKNOWN;
174 if (s->zlibprime_curr || s->zlibprime_prev) {
175 ret = flashsv2_prime(s,
176 s->blocks[blk_idx].pos,
177 s->blocks[blk_idx].size);
181 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
182 s->zstream.avail_in = block_size;
183 s->zstream.next_out = s->tmpblock;
184 s->zstream.avail_out = s->block_size * 3;
185 ret = inflate(&s->zstream, Z_FINISH);
186 if (ret == Z_DATA_ERROR) {
187 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
188 inflateSync(&s->zstream);
189 ret = inflate(&s->zstream, Z_FINISH);
192 if (ret != Z_OK && ret != Z_STREAM_END) {
196 if (s->is_keyframe) {
197 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
198 s->blocks[blk_idx].size = block_size;
200 if (!s->color_depth) {
201 /* Flash Screen Video stores the image upside down, so copy
202 * lines to destination in reverse order. */
203 for (k = 1; k <= s->diff_height; k++) {
204 memcpy(s->frame.data[0] + x_pos * 3 +
205 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
207 /* advance source pointer to next line */
211 /* hybrid 15-bit/palette mode */
212 decode_hybrid(s->tmpblock, s->frame.data[0],
213 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
214 x_pos, s->diff_height, width,
215 s->frame.linesize[0], s->pal);
217 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
221 static int calc_deflate_block_size(int tmpblock_size)
226 zstream.zalloc = Z_NULL;
227 zstream.zfree = Z_NULL;
228 zstream.opaque = Z_NULL;
229 if (deflateInit(&zstream, 0) != Z_OK)
231 size = deflateBound(&zstream, tmpblock_size);
232 deflateEnd(&zstream);
237 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
238 int *got_frame, AVPacket *avpkt)
240 int buf_size = avpkt->size;
241 FlashSVContext *s = avctx->priv_data;
242 int h_blocks, v_blocks, h_part, v_part, i, j, ret;
245 /* no supplementary picture */
251 init_get_bits(&gb, avpkt->data, buf_size * 8);
253 /* start to parse the bitstream */
254 s->block_width = 16 * (get_bits(&gb, 4) + 1);
255 s->image_width = get_bits(&gb, 12);
256 s->block_height = 16 * (get_bits(&gb, 4) + 1);
257 s->image_height = get_bits(&gb, 12);
261 if (get_bits1(&gb)) {
262 avpriv_request_sample(avctx, "iframe");
263 return AVERROR_PATCHWELCOME;
265 if (get_bits1(&gb)) {
266 avpriv_request_sample(avctx, "Custom palette");
267 return AVERROR_PATCHWELCOME;
271 /* calculate number of blocks and size of border (partial) blocks */
272 h_blocks = s->image_width / s->block_width;
273 h_part = s->image_width % s->block_width;
274 v_blocks = s->image_height / s->block_height;
275 v_part = s->image_height % s->block_height;
277 /* the block size could change between frames, make sure the buffer
278 * is large enough, if not, get a larger one */
279 if (s->block_size < s->block_width * s->block_height) {
280 int tmpblock_size = 3 * s->block_width * s->block_height;
282 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
284 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
285 return AVERROR(ENOMEM);
288 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
289 if (s->deflate_block_size <= 0) {
290 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
293 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
294 if (!s->deflate_block) {
295 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
296 return AVERROR(ENOMEM);
300 s->block_size = s->block_width * s->block_height;
302 /* initialize the image size once */
303 if (avctx->width == 0 && avctx->height == 0) {
304 avctx->width = s->image_width;
305 avctx->height = s->image_height;
308 /* check for changes of image width and image height */
309 if (avctx->width != s->image_width || avctx->height != s->image_height) {
310 av_log(avctx, AV_LOG_ERROR,
311 "Frame width or height differs from first frame!\n");
312 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
313 avctx->height, avctx->width, s->image_height, s->image_width);
314 return AVERROR_INVALIDDATA;
317 /* we care for keyframes only in Screen Video v2 */
318 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
319 if (s->is_keyframe) {
320 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
321 memcpy(s->keyframedata, avpkt->data, avpkt->size);
322 s->blocks = av_realloc(s->blocks,
323 (v_blocks + !!v_part) * (h_blocks + !!h_part)
324 * sizeof(s->blocks[0]));
327 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
328 s->image_width, s->image_height, s->block_width, s->block_height,
329 h_blocks, v_blocks, h_part, v_part);
331 if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0) {
332 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
336 /* loop over all block columns */
337 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
339 int y_pos = j * s->block_height; // vertical position in frame
340 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
342 /* loop over all block rows */
343 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
344 int x_pos = i * s->block_width; // horizontal position in frame
345 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
348 /* get the size of the compressed zlib chunk */
349 int size = get_bits(&gb, 16);
352 s->zlibprime_curr = 0;
353 s->zlibprime_prev = 0;
355 s->diff_height = cur_blk_height;
357 if (8 * size > get_bits_left(&gb)) {
358 av_frame_unref(&s->frame);
359 return AVERROR_INVALIDDATA;
362 if (s->ver == 2 && size) {
364 s->color_depth = get_bits(&gb, 2);
365 has_diff = get_bits1(&gb);
366 s->zlibprime_curr = get_bits1(&gb);
367 s->zlibprime_prev = get_bits1(&gb);
369 if (s->color_depth != 0 && s->color_depth != 2) {
370 av_log(avctx, AV_LOG_ERROR,
371 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
372 return AVERROR_INVALIDDATA;
377 av_log(avctx, AV_LOG_ERROR,
378 "inter frame without keyframe\n");
379 return AVERROR_INVALIDDATA;
381 s->diff_start = get_bits(&gb, 8);
382 s->diff_height = get_bits(&gb, 8);
383 av_log(avctx, AV_LOG_DEBUG,
384 "%dx%d diff start %d height %d\n",
385 i, j, s->diff_start, s->diff_height);
389 if (s->zlibprime_prev)
390 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
392 if (s->zlibprime_curr) {
393 int col = get_bits(&gb, 8);
394 int row = get_bits(&gb, 8);
395 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
397 avpriv_request_sample(avctx, "zlibprime_curr");
398 return AVERROR_PATCHWELCOME;
400 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
401 av_log(avctx, AV_LOG_ERROR, "no data available for zlib "
403 return AVERROR_INVALIDDATA;
405 size--; // account for flags byte
410 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
412 for (k = 0; k < cur_blk_height; k++)
413 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
414 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
418 /* skip unchanged blocks, which have size 0 */
420 if (flashsv_decode_block(avctx, avpkt, &gb, size,
421 cur_blk_width, cur_blk_height,
423 i + j * (h_blocks + !!h_part)))
424 av_log(avctx, AV_LOG_ERROR,
425 "error in decompression of block %dx%d\n", i, j);
429 if (s->is_keyframe && s->ver == 2) {
431 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
433 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
434 return AVERROR(ENOMEM);
437 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
440 if ((ret = av_frame_ref(data, &s->frame)) < 0)
445 if ((get_bits_count(&gb) / 8) != buf_size)
446 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
447 buf_size, (get_bits_count(&gb) / 8));
449 /* report that the buffer was completely consumed */
454 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
456 FlashSVContext *s = avctx->priv_data;
457 inflateEnd(&s->zstream);
458 /* release the frame if needed */
459 av_frame_unref(&s->frame);
461 /* free the tmpblock */
462 av_free(s->tmpblock);
468 #if CONFIG_FLASHSV_DECODER
469 AVCodec ff_flashsv_decoder = {
471 .type = AVMEDIA_TYPE_VIDEO,
472 .id = AV_CODEC_ID_FLASHSV,
473 .priv_data_size = sizeof(FlashSVContext),
474 .init = flashsv_decode_init,
475 .close = flashsv_decode_end,
476 .decode = flashsv_decode_frame,
477 .capabilities = CODEC_CAP_DR1,
478 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
479 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
481 #endif /* CONFIG_FLASHSV_DECODER */
483 #if CONFIG_FLASHSV2_DECODER
484 static const uint32_t ff_flashsv2_default_palette[128] = {
485 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
486 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
487 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
488 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
489 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
490 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
491 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
492 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
493 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
494 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
495 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
496 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
497 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
498 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
499 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
500 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
501 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
502 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
503 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
504 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
505 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
509 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
511 FlashSVContext *s = avctx->priv_data;
512 flashsv_decode_init(avctx);
513 s->pal = ff_flashsv2_default_palette;
519 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
521 FlashSVContext *s = avctx->priv_data;
523 av_freep(&s->keyframedata);
524 av_freep(&s->blocks);
525 av_freep(&s->keyframe);
526 av_freep(&s->deflate_block);
527 flashsv_decode_end(avctx);
532 AVCodec ff_flashsv2_decoder = {
534 .type = AVMEDIA_TYPE_VIDEO,
535 .id = AV_CODEC_ID_FLASHSV2,
536 .priv_data_size = sizeof(FlashSVContext),
537 .init = flashsv2_decode_init,
538 .close = flashsv2_decode_end,
539 .decode = flashsv_decode_frame,
540 .capabilities = CODEC_CAP_DR1,
541 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
542 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
544 #endif /* CONFIG_FLASHSV2_DECODER */