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"
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 avcodec_get_frame_defaults(&s->frame);
118 s->frame.data[0] = NULL;
124 static int flashsv2_prime(FlashSVContext *s, uint8_t *src, int size)
127 int zret; // Zlib return code
130 return AVERROR_INVALIDDATA;
136 s->zstream.next_in = src;
137 s->zstream.avail_in = size;
138 s->zstream.next_out = s->tmpblock;
139 s->zstream.avail_out = s->block_size * 3;
140 inflate(&s->zstream, Z_SYNC_FLUSH);
142 if (deflateInit(&zs, 0) != Z_OK)
144 zs.next_in = s->tmpblock;
145 zs.avail_in = s->block_size * 3 - s->zstream.avail_out;
146 zs.next_out = s->deflate_block;
147 zs.avail_out = s->deflate_block_size;
148 deflate(&zs, Z_SYNC_FLUSH);
151 if ((zret = inflateReset(&s->zstream)) != Z_OK) {
152 av_log(s->avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
153 return AVERROR_UNKNOWN;
156 s->zstream.next_in = s->deflate_block;
157 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
158 s->zstream.next_out = s->tmpblock;
159 s->zstream.avail_out = s->block_size * 3;
160 inflate(&s->zstream, Z_SYNC_FLUSH);
165 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
166 GetBitContext *gb, int block_size,
167 int width, int height, int x_pos, int y_pos,
170 struct FlashSVContext *s = avctx->priv_data;
171 uint8_t *line = s->tmpblock;
173 int ret = inflateReset(&s->zstream);
175 av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
176 return AVERROR_UNKNOWN;
178 if (s->zlibprime_curr || s->zlibprime_prev) {
179 ret = flashsv2_prime(s,
180 s->blocks[blk_idx].pos,
181 s->blocks[blk_idx].size);
185 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
186 s->zstream.avail_in = block_size;
187 s->zstream.next_out = s->tmpblock;
188 s->zstream.avail_out = s->block_size * 3;
189 ret = inflate(&s->zstream, Z_FINISH);
190 if (ret == Z_DATA_ERROR) {
191 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
192 inflateSync(&s->zstream);
193 ret = inflate(&s->zstream, Z_FINISH);
196 if (ret != Z_OK && ret != Z_STREAM_END) {
200 if (s->is_keyframe) {
201 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
202 s->blocks[blk_idx].size = block_size;
204 if (!s->color_depth) {
205 /* Flash Screen Video stores the image upside down, so copy
206 * lines to destination in reverse order. */
207 for (k = 1; k <= s->diff_height; k++) {
208 memcpy(s->frame.data[0] + x_pos * 3 +
209 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
211 /* advance source pointer to next line */
215 /* hybrid 15-bit/palette mode */
216 decode_hybrid(s->tmpblock, s->frame.data[0],
217 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
218 x_pos, s->diff_height, width,
219 s->frame.linesize[0], s->pal);
221 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
225 static int calc_deflate_block_size(int tmpblock_size)
230 zstream.zalloc = Z_NULL;
231 zstream.zfree = Z_NULL;
232 zstream.opaque = Z_NULL;
233 if (deflateInit(&zstream, 0) != Z_OK)
235 size = deflateBound(&zstream, tmpblock_size);
236 deflateEnd(&zstream);
241 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
242 int *got_frame, AVPacket *avpkt)
244 int buf_size = avpkt->size;
245 FlashSVContext *s = avctx->priv_data;
246 int h_blocks, v_blocks, h_part, v_part, i, j;
249 /* no supplementary picture */
255 init_get_bits(&gb, avpkt->data, buf_size * 8);
257 /* start to parse the bitstream */
258 s->block_width = 16 * (get_bits(&gb, 4) + 1);
259 s->image_width = get_bits(&gb, 12);
260 s->block_height = 16 * (get_bits(&gb, 4) + 1);
261 s->image_height = get_bits(&gb, 12);
265 if (get_bits1(&gb)) {
266 av_log_missing_feature(avctx, "iframe", 1);
267 return AVERROR_PATCHWELCOME;
269 if (get_bits1(&gb)) {
270 av_log_missing_feature(avctx, "Custom palette", 1);
271 return AVERROR_PATCHWELCOME;
275 /* calculate number of blocks and size of border (partial) blocks */
276 h_blocks = s->image_width / s->block_width;
277 h_part = s->image_width % s->block_width;
278 v_blocks = s->image_height / s->block_height;
279 v_part = s->image_height % s->block_height;
281 /* the block size could change between frames, make sure the buffer
282 * is large enough, if not, get a larger one */
283 if (s->block_size < s->block_width * s->block_height) {
284 int tmpblock_size = 3 * s->block_width * s->block_height;
286 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
288 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
289 return AVERROR(ENOMEM);
292 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
293 if (s->deflate_block_size <= 0) {
294 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
297 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
298 if (!s->deflate_block) {
299 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
300 return AVERROR(ENOMEM);
304 s->block_size = s->block_width * s->block_height;
306 /* initialize the image size once */
307 if (avctx->width == 0 && avctx->height == 0) {
308 avcodec_set_dimensions(avctx, s->image_width, s->image_height);
311 /* check for changes of image width and image height */
312 if (avctx->width != s->image_width || avctx->height != s->image_height) {
313 av_log(avctx, AV_LOG_ERROR,
314 "Frame width or height differs from first frame!\n");
315 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
316 avctx->height, avctx->width, s->image_height, s->image_width);
317 return AVERROR_INVALIDDATA;
320 /* we care for keyframes only in Screen Video v2 */
321 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
322 if (s->is_keyframe) {
323 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
324 memcpy(s->keyframedata, avpkt->data, avpkt->size);
327 s->blocks = av_realloc(s->blocks,
328 (v_blocks + !!v_part) * (h_blocks + !!h_part)
329 * sizeof(s->blocks[0]));
331 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
332 s->image_width, s->image_height, s->block_width, s->block_height,
333 h_blocks, v_blocks, h_part, v_part);
335 s->frame.reference = 3;
336 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
337 FF_BUFFER_HINTS_PRESERVE |
338 FF_BUFFER_HINTS_REUSABLE;
339 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
340 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
344 /* loop over all block columns */
345 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
347 int y_pos = j * s->block_height; // vertical position in frame
348 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
350 /* loop over all block rows */
351 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
352 int x_pos = i * s->block_width; // horizontal position in frame
353 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
356 /* get the size of the compressed zlib chunk */
357 int size = get_bits(&gb, 16);
360 s->zlibprime_curr = 0;
361 s->zlibprime_prev = 0;
363 s->diff_height = cur_blk_height;
365 if (8 * size > get_bits_left(&gb)) {
366 avctx->release_buffer(avctx, &s->frame);
367 s->frame.data[0] = NULL;
368 return AVERROR_INVALIDDATA;
371 if (s->ver == 2 && size) {
373 s->color_depth = get_bits(&gb, 2);
374 has_diff = get_bits1(&gb);
375 s->zlibprime_curr = get_bits1(&gb);
376 s->zlibprime_prev = get_bits1(&gb);
378 if (s->color_depth != 0 && s->color_depth != 2) {
379 av_log(avctx, AV_LOG_ERROR,
380 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
381 return AVERROR_INVALIDDATA;
386 av_log(avctx, AV_LOG_ERROR,
387 "inter frame without keyframe\n");
388 return AVERROR_INVALIDDATA;
390 s->diff_start = get_bits(&gb, 8);
391 s->diff_height = get_bits(&gb, 8);
392 av_log(avctx, AV_LOG_DEBUG,
393 "%dx%d diff start %d height %d\n",
394 i, j, s->diff_start, s->diff_height);
398 if (s->zlibprime_prev)
399 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
401 if (s->zlibprime_curr) {
402 int col = get_bits(&gb, 8);
403 int row = get_bits(&gb, 8);
404 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
406 av_log_missing_feature(avctx, "zlibprime_curr", 1);
407 return AVERROR_PATCHWELCOME;
409 if (!s->blocks && (s->zlibprime_curr || s->zlibprime_prev)) {
410 av_log(avctx, AV_LOG_ERROR, "no data available for zlib "
412 return AVERROR_INVALIDDATA;
414 size--; // account for flags byte
419 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
421 for (k = 0; k < cur_blk_height; k++)
422 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
423 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
427 /* skip unchanged blocks, which have size 0 */
429 if (flashsv_decode_block(avctx, avpkt, &gb, size,
430 cur_blk_width, cur_blk_height,
432 i + j * (h_blocks + !!h_part)))
433 av_log(avctx, AV_LOG_ERROR,
434 "error in decompression of block %dx%d\n", i, j);
438 if (s->is_keyframe && s->ver == 2) {
440 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
442 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
443 return AVERROR(ENOMEM);
446 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
450 *(AVFrame*)data = s->frame;
452 if ((get_bits_count(&gb) / 8) != buf_size)
453 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
454 buf_size, (get_bits_count(&gb) / 8));
456 /* report that the buffer was completely consumed */
461 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
463 FlashSVContext *s = avctx->priv_data;
464 inflateEnd(&s->zstream);
465 /* release the frame if needed */
466 if (s->frame.data[0])
467 avctx->release_buffer(avctx, &s->frame);
469 /* free the tmpblock */
470 av_free(s->tmpblock);
476 #if CONFIG_FLASHSV_DECODER
477 AVCodec ff_flashsv_decoder = {
479 .type = AVMEDIA_TYPE_VIDEO,
480 .id = AV_CODEC_ID_FLASHSV,
481 .priv_data_size = sizeof(FlashSVContext),
482 .init = flashsv_decode_init,
483 .close = flashsv_decode_end,
484 .decode = flashsv_decode_frame,
485 .capabilities = CODEC_CAP_DR1,
486 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
487 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
489 #endif /* CONFIG_FLASHSV_DECODER */
491 #if CONFIG_FLASHSV2_DECODER
492 static const uint32_t ff_flashsv2_default_palette[128] = {
493 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
494 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
495 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
496 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
497 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
498 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
499 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
500 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
501 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
502 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
503 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
504 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
505 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
506 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
507 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
508 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
509 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
510 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
511 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
512 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
513 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
517 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
519 FlashSVContext *s = avctx->priv_data;
520 flashsv_decode_init(avctx);
521 s->pal = ff_flashsv2_default_palette;
527 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
529 FlashSVContext *s = avctx->priv_data;
531 av_freep(&s->keyframedata);
532 av_freep(&s->blocks);
533 av_freep(&s->keyframe);
534 av_freep(&s->deflate_block);
535 flashsv_decode_end(avctx);
540 AVCodec ff_flashsv2_decoder = {
542 .type = AVMEDIA_TYPE_VIDEO,
543 .id = AV_CODEC_ID_FLASHSV2,
544 .priv_data_size = sizeof(FlashSVContext),
545 .init = flashsv2_decode_init,
546 .close = flashsv2_decode_end,
547 .decode = flashsv_decode_frame,
548 .capabilities = CODEC_CAP_DR1,
549 .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
550 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
552 #endif /* CONFIG_FLASHSV2_DECODER */