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 {
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 avcodec_get_frame_defaults(&s->frame);
119 s->frame.data[0] = NULL;
125 static void flashsv2_prime(FlashSVContext *s, uint8_t *src,
126 int size, int unp_size)
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 inflateReset(&s->zstream);
150 s->zstream.next_in = s->deflate_block;
151 s->zstream.avail_in = s->deflate_block_size - zs.avail_out;
152 s->zstream.next_out = s->tmpblock;
153 s->zstream.avail_out = s->block_size * 3;
154 inflate(&s->zstream, Z_SYNC_FLUSH);
157 static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
158 GetBitContext *gb, int block_size,
159 int width, int height, int x_pos, int y_pos,
162 struct FlashSVContext *s = avctx->priv_data;
163 uint8_t *line = s->tmpblock;
165 int ret = inflateReset(&s->zstream);
169 if (s->zlibprime_curr || s->zlibprime_prev) {
170 flashsv2_prime(s, s->blocks[blk_idx].pos, s->blocks[blk_idx].size,
171 s->blocks[blk_idx].unp_size);
173 s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
174 s->zstream.avail_in = block_size;
175 s->zstream.next_out = s->tmpblock;
176 s->zstream.avail_out = s->block_size * 3;
177 ret = inflate(&s->zstream, Z_FINISH);
178 if (ret == Z_DATA_ERROR) {
179 av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
180 inflateSync(&s->zstream);
181 ret = inflate(&s->zstream, Z_FINISH);
184 if (ret != Z_OK && ret != Z_STREAM_END) {
188 if (s->is_keyframe) {
189 s->blocks[blk_idx].pos = s->keyframedata + (get_bits_count(gb) / 8);
190 s->blocks[blk_idx].size = block_size;
191 s->blocks[blk_idx].unp_size = s->block_size * 3 - s->zstream.avail_out;
193 if (!s->color_depth) {
194 /* Flash Screen Video stores the image upside down, so copy
195 * lines to destination in reverse order. */
196 for (k = 1; k <= s->diff_height; k++) {
197 memcpy(s->frame.data[0] + x_pos * 3 +
198 (s->image_height - y_pos - s->diff_start - k) * s->frame.linesize[0],
200 /* advance source pointer to next line */
204 /* hybrid 15-bit/palette mode */
205 decode_hybrid(s->tmpblock, s->frame.data[0],
206 s->image_height - (y_pos + 1 + s->diff_start + s->diff_height),
207 x_pos, s->diff_height, width,
208 s->frame.linesize[0], s->pal);
210 skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
214 static int calc_deflate_block_size(int tmpblock_size)
219 zstream.zalloc = Z_NULL;
220 zstream.zfree = Z_NULL;
221 zstream.opaque = Z_NULL;
222 if (deflateInit(&zstream, 0) != Z_OK)
224 size = deflateBound(&zstream, tmpblock_size);
225 deflateEnd(&zstream);
230 static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
231 int *data_size, AVPacket *avpkt)
233 int buf_size = avpkt->size;
234 FlashSVContext *s = avctx->priv_data;
235 int h_blocks, v_blocks, h_part, v_part, i, j;
238 /* no supplementary picture */
244 init_get_bits(&gb, avpkt->data, buf_size * 8);
246 /* start to parse the bitstream */
247 s->block_width = 16 * (get_bits(&gb, 4) + 1);
248 s->image_width = get_bits(&gb, 12);
249 s->block_height = 16 * (get_bits(&gb, 4) + 1);
250 s->image_height = get_bits(&gb, 12);
254 if (get_bits1(&gb)) {
255 av_log_missing_feature(avctx, "iframe", 1);
256 return AVERROR_PATCHWELCOME;
258 if (get_bits1(&gb)) {
259 av_log_missing_feature(avctx, "custom palette", 1);
260 return AVERROR_PATCHWELCOME;
264 /* calculate number of blocks and size of border (partial) blocks */
265 h_blocks = s->image_width / s->block_width;
266 h_part = s->image_width % s->block_width;
267 v_blocks = s->image_height / s->block_height;
268 v_part = s->image_height % s->block_height;
270 /* the block size could change between frames, make sure the buffer
271 * is large enough, if not, get a larger one */
272 if (s->block_size < s->block_width * s->block_height) {
273 int tmpblock_size = 3 * s->block_width * s->block_height;
275 s->tmpblock = av_realloc(s->tmpblock, tmpblock_size);
277 av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
278 return AVERROR(ENOMEM);
281 s->deflate_block_size = calc_deflate_block_size(tmpblock_size);
282 if (s->deflate_block_size <= 0) {
283 av_log(avctx, AV_LOG_ERROR, "Can't determine deflate buffer size.\n");
286 s->deflate_block = av_realloc(s->deflate_block, s->deflate_block_size);
287 if (!s->deflate_block) {
288 av_log(avctx, AV_LOG_ERROR, "Can't allocate deflate buffer.\n");
289 return AVERROR(ENOMEM);
293 s->block_size = s->block_width * s->block_height;
295 /* initialize the image size once */
296 if (avctx->width == 0 && avctx->height == 0) {
297 avctx->width = s->image_width;
298 avctx->height = s->image_height;
301 /* check for changes of image width and image height */
302 if (avctx->width != s->image_width || avctx->height != s->image_height) {
303 av_log(avctx, AV_LOG_ERROR,
304 "Frame width or height differs from first frame!\n");
305 av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
306 avctx->height, avctx->width, s->image_height, s->image_width);
307 return AVERROR_INVALIDDATA;
310 /* we care for keyframes only in Screen Video v2 */
311 s->is_keyframe = (avpkt->flags & AV_PKT_FLAG_KEY) && (s->ver == 2);
312 if (s->is_keyframe) {
313 s->keyframedata = av_realloc(s->keyframedata, avpkt->size);
314 memcpy(s->keyframedata, avpkt->data, avpkt->size);
315 s->blocks = av_realloc(s->blocks,
316 (v_blocks + !!v_part) * (h_blocks + !!h_part)
317 * sizeof(s->blocks[0]));
320 av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
321 s->image_width, s->image_height, s->block_width, s->block_height,
322 h_blocks, v_blocks, h_part, v_part);
324 s->frame.reference = 3;
325 s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
326 FF_BUFFER_HINTS_PRESERVE |
327 FF_BUFFER_HINTS_REUSABLE;
328 if (avctx->reget_buffer(avctx, &s->frame) < 0) {
329 av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
333 /* loop over all block columns */
334 for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
336 int y_pos = j * s->block_height; // vertical position in frame
337 int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
339 /* loop over all block rows */
340 for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
341 int x_pos = i * s->block_width; // horizontal position in frame
342 int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
345 /* get the size of the compressed zlib chunk */
346 int size = get_bits(&gb, 16);
349 s->zlibprime_curr = 0;
350 s->zlibprime_prev = 0;
352 s->diff_height = cur_blk_height;
354 if (8 * size > get_bits_left(&gb)) {
355 avctx->release_buffer(avctx, &s->frame);
356 s->frame.data[0] = NULL;
357 return AVERROR_INVALIDDATA;
360 if (s->ver == 2 && size) {
362 s->color_depth = get_bits(&gb, 2);
363 has_diff = get_bits1(&gb);
364 s->zlibprime_curr = get_bits1(&gb);
365 s->zlibprime_prev = get_bits1(&gb);
367 if (s->color_depth != 0 && s->color_depth != 2) {
368 av_log(avctx, AV_LOG_ERROR,
369 "%dx%d invalid color depth %d\n", i, j, s->color_depth);
370 return AVERROR_INVALIDDATA;
374 s->diff_start = get_bits(&gb, 8);
375 s->diff_height = get_bits(&gb, 8);
376 av_log(avctx, AV_LOG_DEBUG,
377 "%dx%d diff start %d height %d\n",
378 i, j, s->diff_start, s->diff_height);
382 if (s->zlibprime_prev)
383 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_prev\n", i, j);
385 if (s->zlibprime_curr) {
386 int col = get_bits(&gb, 8);
387 int row = get_bits(&gb, 8);
388 av_log(avctx, AV_LOG_DEBUG, "%dx%d zlibprime_curr %dx%d\n", i, j, col, row);
390 av_log_missing_feature(avctx, "zlibprime_curr", 1);
391 return AVERROR_PATCHWELCOME;
393 size--; // account for flags byte
398 int off = (s->image_height - y_pos - 1) * s->frame.linesize[0];
400 for (k = 0; k < cur_blk_height; k++)
401 memcpy(s->frame.data[0] + off - k*s->frame.linesize[0] + x_pos*3,
402 s->keyframe + off - k*s->frame.linesize[0] + x_pos*3,
406 /* skip unchanged blocks, which have size 0 */
408 if (flashsv_decode_block(avctx, avpkt, &gb, size,
409 cur_blk_width, cur_blk_height,
411 i + j * (h_blocks + !!h_part)))
412 av_log(avctx, AV_LOG_ERROR,
413 "error in decompression of block %dx%d\n", i, j);
417 if (s->is_keyframe && s->ver == 2) {
419 s->keyframe = av_malloc(s->frame.linesize[0] * avctx->height);
421 av_log(avctx, AV_LOG_ERROR, "Cannot allocate image data\n");
422 return AVERROR(ENOMEM);
425 memcpy(s->keyframe, s->frame.data[0], s->frame.linesize[0] * avctx->height);
428 *data_size = sizeof(AVFrame);
429 *(AVFrame*)data = s->frame;
431 if ((get_bits_count(&gb) / 8) != buf_size)
432 av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
433 buf_size, (get_bits_count(&gb) / 8));
435 /* report that the buffer was completely consumed */
440 static av_cold int flashsv_decode_end(AVCodecContext *avctx)
442 FlashSVContext *s = avctx->priv_data;
443 inflateEnd(&s->zstream);
444 /* release the frame if needed */
445 if (s->frame.data[0])
446 avctx->release_buffer(avctx, &s->frame);
448 /* free the tmpblock */
449 av_free(s->tmpblock);
455 #if CONFIG_FLASHSV_DECODER
456 AVCodec ff_flashsv_decoder = {
458 .type = AVMEDIA_TYPE_VIDEO,
459 .id = CODEC_ID_FLASHSV,
460 .priv_data_size = sizeof(FlashSVContext),
461 .init = flashsv_decode_init,
462 .close = flashsv_decode_end,
463 .decode = flashsv_decode_frame,
464 .capabilities = CODEC_CAP_DR1,
465 .pix_fmts = (const enum PixelFormat[]){ PIX_FMT_BGR24, PIX_FMT_NONE },
466 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
468 #endif /* CONFIG_FLASHSV_DECODER */
470 #if CONFIG_FLASHSV2_DECODER
471 static const uint32_t ff_flashsv2_default_palette[128] = {
472 0x000000, 0x333333, 0x666666, 0x999999, 0xCCCCCC, 0xFFFFFF,
473 0x330000, 0x660000, 0x990000, 0xCC0000, 0xFF0000, 0x003300,
474 0x006600, 0x009900, 0x00CC00, 0x00FF00, 0x000033, 0x000066,
475 0x000099, 0x0000CC, 0x0000FF, 0x333300, 0x666600, 0x999900,
476 0xCCCC00, 0xFFFF00, 0x003333, 0x006666, 0x009999, 0x00CCCC,
477 0x00FFFF, 0x330033, 0x660066, 0x990099, 0xCC00CC, 0xFF00FF,
478 0xFFFF33, 0xFFFF66, 0xFFFF99, 0xFFFFCC, 0xFF33FF, 0xFF66FF,
479 0xFF99FF, 0xFFCCFF, 0x33FFFF, 0x66FFFF, 0x99FFFF, 0xCCFFFF,
480 0xCCCC33, 0xCCCC66, 0xCCCC99, 0xCCCCFF, 0xCC33CC, 0xCC66CC,
481 0xCC99CC, 0xCCFFCC, 0x33CCCC, 0x66CCCC, 0x99CCCC, 0xFFCCCC,
482 0x999933, 0x999966, 0x9999CC, 0x9999FF, 0x993399, 0x996699,
483 0x99CC99, 0x99FF99, 0x339999, 0x669999, 0xCC9999, 0xFF9999,
484 0x666633, 0x666699, 0x6666CC, 0x6666FF, 0x663366, 0x669966,
485 0x66CC66, 0x66FF66, 0x336666, 0x996666, 0xCC6666, 0xFF6666,
486 0x333366, 0x333399, 0x3333CC, 0x3333FF, 0x336633, 0x339933,
487 0x33CC33, 0x33FF33, 0x663333, 0x993333, 0xCC3333, 0xFF3333,
488 0x003366, 0x336600, 0x660033, 0x006633, 0x330066, 0x663300,
489 0x336699, 0x669933, 0x993366, 0x339966, 0x663399, 0x996633,
490 0x6699CC, 0x99CC66, 0xCC6699, 0x66CC99, 0x9966CC, 0xCC9966,
491 0x99CCFF, 0xCCFF99, 0xFF99CC, 0x99FFCC, 0xCC99FF, 0xFFCC99,
492 0x111111, 0x222222, 0x444444, 0x555555, 0xAAAAAA, 0xBBBBBB,
496 static av_cold int flashsv2_decode_init(AVCodecContext *avctx)
498 FlashSVContext *s = avctx->priv_data;
499 flashsv_decode_init(avctx);
500 s->pal = ff_flashsv2_default_palette;
506 static av_cold int flashsv2_decode_end(AVCodecContext *avctx)
508 FlashSVContext *s = avctx->priv_data;
510 av_freep(&s->keyframedata);
511 av_freep(&s->blocks);
512 av_freep(&s->keyframe);
513 av_freep(&s->deflate_block);
514 flashsv_decode_end(avctx);
519 AVCodec ff_flashsv2_decoder = {
521 .type = AVMEDIA_TYPE_VIDEO,
522 .id = CODEC_ID_FLASHSV2,
523 .priv_data_size = sizeof(FlashSVContext),
524 .init = flashsv2_decode_init,
525 .close = flashsv2_decode_end,
526 .decode = flashsv_decode_frame,
527 .capabilities = CODEC_CAP_DR1,
528 .pix_fmts = (const enum PixelFormat[]){ PIX_FMT_BGR24, PIX_FMT_NONE },
529 .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v2"),
531 #endif /* CONFIG_FLASHSV2_DECODER */