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 = PIX_FMT_BGR24;
118 s->frame.data[0] = NULL;
124 static void flashsv2_prime(FlashSVContext *s, uint8_t *src,
125 int size, int unp_size)
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 inflateReset(&s->zstream);
149 s->zstream.next_in = s->deflate_block;
150 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
151 s->zstream.next_out = s->tmpblock;
152 s->zstream.avail_out = s->block_size * 3;
153 inflate(&s->zstream, Z_SYNC_FLUSH);
156 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
157 GetBitContext *gb, int block_size,
158 int width, int height, int x_pos, int y_pos,
161 struct FlashSVContext *s = avctx->priv_data;
162 uint8_t *line = s->tmpblock;
164 int ret = inflateReset(&s->zstream);
168 if (s->zlibprime_curr || s->zlibprime_prev) {
169 flashsv2_prime(s, s->blocks[blk_idx].pos, s->blocks[blk_idx].size,
170 s->blocks[blk_idx].unp_size);
172 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
173 s->zstream.avail_in = block_size;
174 s->zstream.next_out = s->tmpblock;
175 s->zstream.avail_out = s->block_size * 3;
176 ret = inflate(&s->zstream, Z_FINISH);
177 if (ret == Z_DATA_ERROR) {
178 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
179 inflateSync(&s->zstream);
180 ret = inflate(&s->zstream, Z_FINISH);
183 if (ret != Z_OK && ret != Z_STREAM_END) {
187 if (s->is_keyframe) {
188 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
189 s->blocks[blk_idx].size = block_size;
190 s->blocks[blk_idx].unp_size = s->block_size * 3 - s->zstream.avail_out;
192 if (!s->color_depth) {
193 /* Flash Screen Video stores the image upside down, so copy
194 * lines to destination in reverse order. */
195 for (k = 1; k <= s->diff_height; k++) {
196 memcpy(s->frame.data[0] + x_pos * 3 +
197 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
199 /* advance source pointer to next line */
203 /* hybrid 15-bit/palette mode */
204 decode_hybrid(s->tmpblock, s->frame.data[0],
205 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
206 x_pos, s->diff_height, width,
207 s->frame.linesize[0], s->pal);
209 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
213 static int calc_deflate_block_size(int tmpblock_size)
218 zstream.zalloc = Z_NULL;
219 zstream.zfree = Z_NULL;
220 zstream.opaque = Z_NULL;
221 if (deflateInit(&zstream, 0) != Z_OK)
223 size = deflateBound(&zstream, tmpblock_size);
224 deflateEnd(&zstream);
229 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
230 int *data_size, AVPacket *avpkt)
232 int buf_size = avpkt->size;
233 FlashSVContext *s = avctx->priv_data;
234 int h_blocks, v_blocks, h_part, v_part, i, j;
237 /* no supplementary picture */
243 init_get_bits(&gb, avpkt->data, buf_size * 8);
245 /* start to parse the bitstream */
246 s->block_width = 16 * (get_bits(&gb, 4) + 1);
247 s->image_width = get_bits(&gb, 12);
248 s->block_height = 16 * (get_bits(&gb, 4) + 1);
249 s->image_height = get_bits(&gb, 12);
253 if (get_bits1(&gb)) {
254 av_log_missing_feature(avctx, "iframe", 1);
255 return AVERROR_PATCHWELCOME;
257 if (get_bits1(&gb)) {
258 av_log_missing_feature(avctx, "custom palette", 1);
259 return AVERROR_PATCHWELCOME;
263 /* calculate number of blocks and size of border (partial) blocks */
264 h_blocks = s->image_width / s->block_width;
265 h_part = s->image_width % s->block_width;
266 v_blocks = s->image_height / s->block_height;
267 v_part = s->image_height % s->block_height;
269 /* the block size could change between frames, make sure the buffer
270 * is large enough, if not, get a larger one */
271 if (s->block_size < s->block_width * s->block_height) {
272 int tmpblock_size = 3 * s->block_width * s->block_height;
274 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
276 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
277 return AVERROR(ENOMEM);
280 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
281 if (s->deflate_block_size <= 0) {
282 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
285 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
286 if (!s->deflate_block) {
287 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
288 return AVERROR(ENOMEM);
292 s->block_size = s->block_width * s->block_height;
294 /* initialize the image size once */
295 if (avctx->width == 0 && avctx->height == 0) {
296 avctx->width = s->image_width;
297 avctx->height = s->image_height;
300 /* check for changes of image width and image height */
301 if (avctx->width != s->image_width || avctx->height != s->image_height) {
302 av_log(avctx, AV_LOG_ERROR,
303 "Frame width or height differs from first frames!\n");
304 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
305 avctx->height, avctx->width, s->image_height, s->image_width);
306 return AVERROR_INVALIDDATA;
309 /* we care for keyframes only in Screen Video v2 */
310 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
311 if (s->is_keyframe) {
312 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
313 memcpy(s->keyframedata, avpkt->data, avpkt->size);
314 s->blocks = av_realloc(s->blocks,
315 (v_blocks + !!v_part) * (h_blocks + !!h_part)
316 * sizeof(s->blocks[0]));
319 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
320 s->image_width, s->image_height, s->block_width, s->block_height,
321 h_blocks, v_blocks, h_part, v_part);
323 s->frame.reference = 3;
324 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
325 FF_BUFFER_HINTS_PRESERVE |
326 FF_BUFFER_HINTS_REUSABLE;
327 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
328 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
332 /* loop over all block columns */
333 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
335 int y_pos = j * s->block_height; // vertical position in frame
336 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
338 /* loop over all block rows */
339 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
340 int x_pos = i * s->block_width; // horizontal position in frame
341 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
344 /* get the size of the compressed zlib chunk */
345 int size = get_bits(&gb, 16);
348 s->zlibprime_curr = 0;
349 s->zlibprime_prev = 0;
351 s->diff_height = cur_blk_height;
353 if (8 * size > get_bits_left(&gb)) {
354 avctx->release_buffer(avctx, &s->frame);
355 s->frame.data[0] = NULL;
356 return AVERROR_INVALIDDATA;
359 if (s->ver == 2 && size) {
361 s->color_depth = get_bits(&gb, 2);
362 has_diff = get_bits1(&gb);
363 s->zlibprime_curr = get_bits1(&gb);
364 s->zlibprime_prev = get_bits1(&gb);
366 if (s->color_depth != 0 && s->color_depth != 2) {
367 av_log(avctx, AV_LOG_ERROR,
368 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
373 s->diff_start = get_bits(&gb, 8);
374 s->diff_height = get_bits(&gb, 8);
375 av_log(avctx, AV_LOG_DEBUG,
376 "%dx%d diff start %d height %d\n",
377 i, j, s->diff_start, s->diff_height);
381 if (s->zlibprime_prev)
382 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
384 if (s->zlibprime_curr) {
385 int col = get_bits(&gb, 8);
386 int row = get_bits(&gb, 8);
387 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
389 av_log_missing_feature(avctx, "zlibprime_curr", 1);
390 return AVERROR_PATCHWELCOME;
392 size--; // account for flags byte
397 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
399 for (k = 0; k < cur_blk_height; k++)
400 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
401 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
405 /* skip unchanged blocks, which have size 0 */
407 if (flashsv_decode_block(avctx, avpkt, &gb, size,
408 cur_blk_width, cur_blk_height,
410 i + j * (h_blocks + !!h_part)))
411 av_log(avctx, AV_LOG_ERROR,
412 "error in decompression of block %dx%d\n", i, j);
416 if (s->is_keyframe && s->ver == 2) {
418 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
420 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
421 return AVERROR(ENOMEM);
424 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
427 *data_size = sizeof(AVFrame);
428 *(AVFrame*)data = s->frame;
430 if ((get_bits_count(&gb) / 8) != buf_size)
431 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
432 buf_size, (get_bits_count(&gb) / 8));
434 /* report that the buffer was completely consumed */
439 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
441 FlashSVContext *s = avctx->priv_data;
442 inflateEnd(&s->zstream);
443 /* release the frame if needed */
444 if (s->frame.data[0])
445 avctx->release_buffer(avctx, &s->frame);
447 /* free the tmpblock */
448 av_free(s->tmpblock);
454 #if CONFIG_FLASHSV_DECODER
455 AVCodec ff_flashsv_decoder = {
457 .type = AVMEDIA_TYPE_VIDEO,
458 .id = CODEC_ID_FLASHSV,
459 .priv_data_size = sizeof(FlashSVContext),
460 .init = flashsv_decode_init,
461 .close = flashsv_decode_end,
462 .decode = flashsv_decode_frame,
463 .capabilities = CODEC_CAP_DR1,
464 .pix_fmts = (const enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_NONE},
465 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
467 #endif /* CONFIG_FLASHSV_DECODER */
469 #if CONFIG_FLASHSV2_DECODER
470 static const uint32_t ff_flashsv2_default_palette[128] = {
471 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
472 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
473 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
474 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
475 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
476 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
477 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
478 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
479 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
480 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
481 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
482 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
483 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
484 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
485 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
486 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
487 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
488 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
489 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
490 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
491 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
495 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
497 FlashSVContext *s = avctx->priv_data;
498 flashsv_decode_init(avctx);
499 s->pal = ff_flashsv2_default_palette;
505 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
507 FlashSVContext *s = avctx->priv_data;
509 av_freep(&s->keyframedata);
510 av_freep(&s->blocks);
511 av_freep(&s->keyframe);
512 av_freep(&s->deflate_block);
513 flashsv_decode_end(avctx);
518 AVCodec ff_flashsv2_decoder = {
520 .type = AVMEDIA_TYPE_VIDEO,
521 .id = CODEC_ID_FLASHSV2,
522 .priv_data_size = sizeof(FlashSVContext),
523 .init = flashsv2_decode_init,
524 .close = flashsv2_decode_end,
525 .decode = flashsv_decode_frame,
526 .capabilities = CODEC_CAP_DR1,
527 .pix_fmts = (const enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_NONE},
528 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
530 #endif /* CONFIG_FLASHSV2_DECODER */