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 {
50 typedef struct FlashSVContext {
51 AVCodecContext *avctx;
53 int image_width, image_height;
54 int block_width, block_height;
61 uint8_t *keyframedata;
64 uint8_t *deflate_block;
65 int deflate_block_size;
67 int zlibprime_curr, zlibprime_prev;
68 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 s->frame.data[0] = NULL;
123 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
126 int zret; // Zlib return code
132 s->zstream.next_in = src;
133 s->zstream.avail_in = size;
134 s->zstream.next_out = s->tmpblock;
135 s->zstream.avail_out = s->block_size * 3;
136 inflate(&s->zstream, Z_SYNC_FLUSH);
139 zs.next_in = s->tmpblock;
140 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
141 zs.next_out = s->deflate_block;
142 zs.avail_out = s->deflate_block_size;
143 deflate(&zs, Z_SYNC_FLUSH);
146 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
147 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
148 return AVERROR_UNKNOWN;
151 s->zstream.next_in = s->deflate_block;
152 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
153 s->zstream.next_out = s->tmpblock;
154 s->zstream.avail_out = s->block_size * 3;
155 inflate(&s->zstream, Z_SYNC_FLUSH);
160 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
161 GetBitContext *gb, int block_size,
162 int width, int height, int x_pos, int y_pos,
165 struct FlashSVContext *s = avctx->priv_data;
166 uint8_t *line = s->tmpblock;
168 int ret = inflateReset(&s->zstream);
170 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
171 return AVERROR_UNKNOWN;
173 if (s->zlibprime_curr || s->zlibprime_prev) {
174 ret = flashsv2_prime(s,
175 s->blocks[blk_idx].pos,
176 s->blocks[blk_idx].size);
180 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
181 s->zstream.avail_in = block_size;
182 s->zstream.next_out = s->tmpblock;
183 s->zstream.avail_out = s->block_size * 3;
184 ret = inflate(&s->zstream, Z_FINISH);
185 if (ret == Z_DATA_ERROR) {
186 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
187 inflateSync(&s->zstream);
188 ret = inflate(&s->zstream, Z_FINISH);
191 if (ret != Z_OK && ret != Z_STREAM_END) {
195 if (s->is_keyframe) {
196 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
197 s->blocks[blk_idx].size = block_size;
199 if (!s->color_depth) {
200 /* Flash Screen Video stores the image upside down, so copy
201 * lines to destination in reverse order. */
202 for (k = 1; k <= s->diff_height; k++) {
203 memcpy(s->frame.data[0] + x_pos * 3 +
204 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
206 /* advance source pointer to next line */
210 /* hybrid 15-bit/palette mode */
211 decode_hybrid(s->tmpblock, s->frame.data[0],
212 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
213 x_pos, s->diff_height, width,
214 s->frame.linesize[0], s->pal);
216 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
220 static int calc_deflate_block_size(int tmpblock_size)
225 zstream.zalloc = Z_NULL;
226 zstream.zfree = Z_NULL;
227 zstream.opaque = Z_NULL;
228 if (deflateInit(&zstream, 0) != Z_OK)
230 size = deflateBound(&zstream, tmpblock_size);
231 deflateEnd(&zstream);
236 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
237 int *data_size, AVPacket *avpkt)
239 int buf_size = avpkt->size;
240 FlashSVContext *s = avctx->priv_data;
241 int h_blocks, v_blocks, h_part, v_part, i, j;
244 /* no supplementary picture */
250 init_get_bits(&gb, avpkt->data, buf_size * 8);
252 /* start to parse the bitstream */
253 s->block_width = 16 * (get_bits(&gb, 4) + 1);
254 s->image_width = get_bits(&gb, 12);
255 s->block_height = 16 * (get_bits(&gb, 4) + 1);
256 s->image_height = get_bits(&gb, 12);
260 if (get_bits1(&gb)) {
261 av_log_missing_feature(avctx, "iframe", 1);
262 return AVERROR_PATCHWELCOME;
264 if (get_bits1(&gb)) {
265 av_log_missing_feature(avctx, "Custom palette", 1);
266 return AVERROR_PATCHWELCOME;
270 /* calculate number of blocks and size of border (partial) blocks */
271 h_blocks = s->image_width / s->block_width;
272 h_part = s->image_width % s->block_width;
273 v_blocks = s->image_height / s->block_height;
274 v_part = s->image_height % s->block_height;
276 /* the block size could change between frames, make sure the buffer
277 * is large enough, if not, get a larger one */
278 if (s->block_size < s->block_width * s->block_height) {
279 int tmpblock_size = 3 * s->block_width * s->block_height;
281 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
283 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
284 return AVERROR(ENOMEM);
287 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
288 if (s->deflate_block_size <= 0) {
289 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
292 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
293 if (!s->deflate_block) {
294 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
295 return AVERROR(ENOMEM);
299 s->block_size = s->block_width * s->block_height;
301 /* initialize the image size once */
302 if (avctx->width == 0 && avctx->height == 0) {
303 avctx->width = s->image_width;
304 avctx->height = s->image_height;
307 /* check for changes of image width and image height */
308 if (avctx->width != s->image_width || avctx->height != s->image_height) {
309 av_log(avctx, AV_LOG_ERROR,
310 "Frame width or height differs from first frame!\n");
311 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
312 avctx->height, avctx->width, s->image_height, s->image_width);
313 return AVERROR_INVALIDDATA;
316 /* we care for keyframes only in Screen Video v2 */
317 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
318 if (s->is_keyframe) {
319 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
320 memcpy(s->keyframedata, avpkt->data, avpkt->size);
321 s->blocks = av_realloc(s->blocks,
322 (v_blocks + !!v_part) * (h_blocks + !!h_part)
323 * sizeof(s->blocks[0]));
326 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
327 s->image_width, s->image_height, s->block_width, s->block_height,
328 h_blocks, v_blocks, h_part, v_part);
330 s->frame.reference = 3;
331 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
332 FF_BUFFER_HINTS_PRESERVE |
333 FF_BUFFER_HINTS_REUSABLE;
334 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
335 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
339 /* loop over all block columns */
340 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
342 int y_pos = j * s->block_height; // vertical position in frame
343 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
345 /* loop over all block rows */
346 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
347 int x_pos = i * s->block_width; // horizontal position in frame
348 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
351 /* get the size of the compressed zlib chunk */
352 int size = get_bits(&gb, 16);
355 s->zlibprime_curr = 0;
356 s->zlibprime_prev = 0;
358 s->diff_height = cur_blk_height;
360 if (8 * size > get_bits_left(&gb)) {
361 avctx->release_buffer(avctx, &s->frame);
362 s->frame.data[0] = NULL;
363 return AVERROR_INVALIDDATA;
366 if (s->ver == 2 && size) {
368 s->color_depth = get_bits(&gb, 2);
369 has_diff = get_bits1(&gb);
370 s->zlibprime_curr = get_bits1(&gb);
371 s->zlibprime_prev = get_bits1(&gb);
373 if (s->color_depth != 0 && s->color_depth != 2) {
374 av_log(avctx, AV_LOG_ERROR,
375 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
376 return AVERROR_INVALIDDATA;
380 s->diff_start = get_bits(&gb, 8);
381 s->diff_height = get_bits(&gb, 8);
382 av_log(avctx, AV_LOG_DEBUG,
383 "%dx%d diff start %d height %d\n",
384 i, j, s->diff_start, s->diff_height);
388 if (s->zlibprime_prev)
389 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
391 if (s->zlibprime_curr) {
392 int col = get_bits(&gb, 8);
393 int row = get_bits(&gb, 8);
394 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
396 av_log_missing_feature(avctx, "zlibprime_curr", 1);
397 return AVERROR_PATCHWELCOME;
399 size--; // account for flags byte
404 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
406 for (k = 0; k < cur_blk_height; k++)
407 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
408 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
412 /* skip unchanged blocks, which have size 0 */
414 if (flashsv_decode_block(avctx, avpkt, &gb, size,
415 cur_blk_width, cur_blk_height,
417 i + j * (h_blocks + !!h_part)))
418 av_log(avctx, AV_LOG_ERROR,
419 "error in decompression of block %dx%d\n", i, j);
423 if (s->is_keyframe && s->ver == 2) {
425 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
427 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
428 return AVERROR(ENOMEM);
431 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
434 *data_size = sizeof(AVFrame);
435 *(AVFrame*)data = s->frame;
437 if ((get_bits_count(&gb) / 8) != buf_size)
438 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
439 buf_size, (get_bits_count(&gb) / 8));
441 /* report that the buffer was completely consumed */
446 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
448 FlashSVContext *s = avctx->priv_data;
449 inflateEnd(&s->zstream);
450 /* release the frame if needed */
451 if (s->frame.data[0])
452 avctx->release_buffer(avctx, &s->frame);
454 /* free the tmpblock */
455 av_free(s->tmpblock);
461 #if CONFIG_FLASHSV_DECODER
462 AVCodec ff_flashsv_decoder = {
464 .type = AVMEDIA_TYPE_VIDEO,
465 .id = AV_CODEC_ID_FLASHSV,
466 .priv_data_size = sizeof(FlashSVContext),
467 .init = flashsv_decode_init,
468 .close = flashsv_decode_end,
469 .decode = flashsv_decode_frame,
470 .capabilities = CODEC_CAP_DR1,
471 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
472 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
474 #endif /* CONFIG_FLASHSV_DECODER */
476 #if CONFIG_FLASHSV2_DECODER
477 static const uint32_t ff_flashsv2_default_palette[128] = {
478 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
479 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
480 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
481 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
482 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
483 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
484 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
485 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
486 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
487 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
488 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
489 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
490 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
491 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
492 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
493 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
494 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
495 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
496 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
497 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
498 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
502 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
504 FlashSVContext *s = avctx->priv_data;
505 flashsv_decode_init(avctx);
506 s->pal = ff_flashsv2_default_palette;
512 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
514 FlashSVContext *s = avctx->priv_data;
516 av_freep(&s->keyframedata);
517 av_freep(&s->blocks);
518 av_freep(&s->keyframe);
519 av_freep(&s->deflate_block);
520 flashsv_decode_end(avctx);
525 AVCodec ff_flashsv2_decoder = {
527 .type = AVMEDIA_TYPE_VIDEO,
528 .id = AV_CODEC_ID_FLASHSV2,
529 .priv_data_size = sizeof(FlashSVContext),
530 .init = flashsv2_decode_init,
531 .close = flashsv2_decode_end,
532 .decode = flashsv_decode_frame,
533 .capabilities = CODEC_CAP_DR1,
534 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
535 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
537 #endif /* CONFIG_FLASHSV2_DECODER */