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"
45 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 s->frame.data[0] = NULL;
124 static int flashsv2_prime(FlashSVContext *s, uint8_t *src,
125 int size, int unp_size)
128 int zret; // Zlib return code
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);
141 zs.next_in = s->tmpblock;
142 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
143 zs.next_out = s->deflate_block;
144 zs.avail_out = s->deflate_block_size;
145 deflate(&zs, Z_SYNC_FLUSH);
148 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
149 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
150 return AVERROR_UNKNOWN;
153 s->zstream.next_in = s->deflate_block;
154 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
155 s->zstream.next_out = s->tmpblock;
156 s->zstream.avail_out = s->block_size * 3;
157 inflate(&s->zstream, Z_SYNC_FLUSH);
162 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
163 GetBitContext *gb, int block_size,
164 int width, int height, int x_pos, int y_pos,
167 struct FlashSVContext *s = avctx->priv_data;
168 uint8_t *line = s->tmpblock;
170 int ret = inflateReset(&s->zstream);
172 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
173 return AVERROR_UNKNOWN;
175 if (s->zlibprime_curr || s->zlibprime_prev) {
176 ret = flashsv2_prime(s, s->blocks[blk_idx].pos, s->blocks[blk_idx].size,
177 s->blocks[blk_idx].unp_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;
199 s->blocks[blk_idx].unp_size = s->block_size * 3 - s->zstream.avail_out;
201 if (!s->color_depth) {
202 /* Flash Screen Video stores the image upside down, so copy
203 * lines to destination in reverse order. */
204 for (k = 1; k <= s->diff_height; k++) {
205 memcpy(s->frame.data[0] + x_pos * 3 +
206 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
208 /* advance source pointer to next line */
212 /* hybrid 15-bit/palette mode */
213 decode_hybrid(s->tmpblock, s->frame.data[0],
214 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
215 x_pos, s->diff_height, width,
216 s->frame.linesize[0], s->pal);
218 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
222 static int calc_deflate_block_size(int tmpblock_size)
227 zstream.zalloc = Z_NULL;
228 zstream.zfree = Z_NULL;
229 zstream.opaque = Z_NULL;
230 if (deflateInit(&zstream, 0) != Z_OK)
232 size = deflateBound(&zstream, tmpblock_size);
233 deflateEnd(&zstream);
238 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
239 int *data_size, AVPacket *avpkt)
241 int buf_size = avpkt->size;
242 FlashSVContext *s = avctx->priv_data;
243 int h_blocks, v_blocks, h_part, v_part, i, j;
246 /* no supplementary picture */
252 init_get_bits(&gb, avpkt->data, buf_size * 8);
254 /* start to parse the bitstream */
255 s->block_width = 16 * (get_bits(&gb, 4) + 1);
256 s->image_width = get_bits(&gb, 12);
257 s->block_height = 16 * (get_bits(&gb, 4) + 1);
258 s->image_height = get_bits(&gb, 12);
262 if (get_bits1(&gb)) {
263 av_log_missing_feature(avctx, "iframe", 1);
264 return AVERROR_PATCHWELCOME;
266 if (get_bits1(&gb)) {
267 av_log_missing_feature(avctx, "custom palette", 1);
268 return AVERROR_PATCHWELCOME;
272 /* calculate number of blocks and size of border (partial) blocks */
273 h_blocks = s->image_width / s->block_width;
274 h_part = s->image_width % s->block_width;
275 v_blocks = s->image_height / s->block_height;
276 v_part = s->image_height % s->block_height;
278 /* the block size could change between frames, make sure the buffer
279 * is large enough, if not, get a larger one */
280 if (s->block_size < s->block_width * s->block_height) {
281 int tmpblock_size = 3 * s->block_width * s->block_height;
283 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
285 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
286 return AVERROR(ENOMEM);
289 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
290 if (s->deflate_block_size <= 0) {
291 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
294 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
295 if (!s->deflate_block) {
296 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
297 return AVERROR(ENOMEM);
301 s->block_size = s->block_width * s->block_height;
303 /* initialize the image size once */
304 if (avctx->width == 0 && avctx->height == 0) {
305 avctx->width = s->image_width;
306 avctx->height = s->image_height;
309 /* check for changes of image width and image height */
310 if (avctx->width != s->image_width || avctx->height != s->image_height) {
311 av_log(avctx, AV_LOG_ERROR,
312 "Frame width or height differs from first frame!\n");
313 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
314 avctx->height, avctx->width, s->image_height, s->image_width);
315 return AVERROR_INVALIDDATA;
318 /* we care for keyframes only in Screen Video v2 */
319 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
320 if (s->is_keyframe) {
321 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
322 memcpy(s->keyframedata, avpkt->data, avpkt->size);
323 s->blocks = av_realloc(s->blocks,
324 (v_blocks + !!v_part) * (h_blocks + !!h_part)
325 * sizeof(s->blocks[0]));
328 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
329 s->image_width, s->image_height, s->block_width, s->block_height,
330 h_blocks, v_blocks, h_part, v_part);
332 s->frame.reference = 3;
333 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
334 FF_BUFFER_HINTS_PRESERVE |
335 FF_BUFFER_HINTS_REUSABLE;
336 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
337 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
341 /* loop over all block columns */
342 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
344 int y_pos = j * s->block_height; // vertical position in frame
345 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
347 /* loop over all block rows */
348 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
349 int x_pos = i * s->block_width; // horizontal position in frame
350 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
353 /* get the size of the compressed zlib chunk */
354 int size = get_bits(&gb, 16);
357 s->zlibprime_curr = 0;
358 s->zlibprime_prev = 0;
360 s->diff_height = cur_blk_height;
362 if (8 * size > get_bits_left(&gb)) {
363 avctx->release_buffer(avctx, &s->frame);
364 s->frame.data[0] = NULL;
365 return AVERROR_INVALIDDATA;
368 if (s->ver == 2 && size) {
370 s->color_depth = get_bits(&gb, 2);
371 has_diff = get_bits1(&gb);
372 s->zlibprime_curr = get_bits1(&gb);
373 s->zlibprime_prev = get_bits1(&gb);
375 if (s->color_depth != 0 && s->color_depth != 2) {
376 av_log(avctx, AV_LOG_ERROR,
377 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
378 return AVERROR_INVALIDDATA;
382 s->diff_start = get_bits(&gb, 8);
383 s->diff_height = get_bits(&gb, 8);
384 av_log(avctx, AV_LOG_DEBUG,
385 "%dx%d diff start %d height %d\n",
386 i, j, s->diff_start, s->diff_height);
390 if (s->zlibprime_prev)
391 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
393 if (s->zlibprime_curr) {
394 int col = get_bits(&gb, 8);
395 int row = get_bits(&gb, 8);
396 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
398 av_log_missing_feature(avctx, "zlibprime_curr", 1);
399 return AVERROR_PATCHWELCOME;
401 size--; // account for flags byte
406 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
408 for (k = 0; k < cur_blk_height; k++)
409 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
410 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
414 /* skip unchanged blocks, which have size 0 */
416 if (flashsv_decode_block(avctx, avpkt, &gb, size,
417 cur_blk_width, cur_blk_height,
419 i + j * (h_blocks + !!h_part)))
420 av_log(avctx, AV_LOG_ERROR,
421 "error in decompression of block %dx%d\n", i, j);
425 if (s->is_keyframe && s->ver == 2) {
427 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
429 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
430 return AVERROR(ENOMEM);
433 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
436 *data_size = sizeof(AVFrame);
437 *(AVFrame*)data = s->frame;
439 if ((get_bits_count(&gb) / 8) != buf_size)
440 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
441 buf_size, (get_bits_count(&gb) / 8));
443 /* report that the buffer was completely consumed */
448 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
450 FlashSVContext *s = avctx->priv_data;
451 inflateEnd(&s->zstream);
452 /* release the frame if needed */
453 if (s->frame.data[0])
454 avctx->release_buffer(avctx, &s->frame);
456 /* free the tmpblock */
457 av_free(s->tmpblock);
463 #if CONFIG_FLASHSV_DECODER
464 AVCodec ff_flashsv_decoder = {
466 .type = AVMEDIA_TYPE_VIDEO,
467 .id = AV_CODEC_ID_FLASHSV,
468 .priv_data_size = sizeof(FlashSVContext),
469 .init = flashsv_decode_init,
470 .close = flashsv_decode_end,
471 .decode = flashsv_decode_frame,
472 .capabilities = CODEC_CAP_DR1,
473 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
474 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
476 #endif /* CONFIG_FLASHSV_DECODER */
478 #if CONFIG_FLASHSV2_DECODER
479 static const uint32_t ff_flashsv2_default_palette[128] = {
480 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
481 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
482 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
483 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
484 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
485 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
486 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
487 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
488 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
489 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
490 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
491 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
492 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
493 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
494 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
495 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
496 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
497 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
498 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
499 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
500 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
504 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
506 FlashSVContext *s = avctx->priv_data;
507 flashsv_decode_init(avctx);
508 s->pal = ff_flashsv2_default_palette;
514 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
516 FlashSVContext *s = avctx->priv_data;
518 av_freep(&s->keyframedata);
519 av_freep(&s->blocks);
520 av_freep(&s->keyframe);
521 av_freep(&s->deflate_block);
522 flashsv_decode_end(avctx);
527 AVCodec ff_flashsv2_decoder = {
529 .type = AVMEDIA_TYPE_VIDEO,
530 .id = AV_CODEC_ID_FLASHSV2,
531 .priv_data_size = sizeof(FlashSVContext),
532 .init = flashsv2_decode_init,
533 .close = flashsv2_decode_end,
534 .decode = flashsv_decode_frame,
535 .capabilities = CODEC_CAP_DR1,
536 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
537 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
539 #endif /* CONFIG_FLASHSV2_DECODER */