mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-11-21 10:55:51 +02:00
244 lines
8.3 KiB
C
244 lines
8.3 KiB
C
/*
|
|
* Flash Screen Video decoder
|
|
* Copyright (C) 2004 Alex Beregszaszi
|
|
* Copyright (C) 2006 Benjamin Larsson
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* Libav is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
/**
|
|
* @file
|
|
* Flash Screen Video decoder
|
|
* @author Alex Beregszaszi
|
|
* @author Benjamin Larsson
|
|
*
|
|
* A description of the bitstream format for Flash Screen Video version 1/2
|
|
* is part of the SWF File Format Specification (version 10), which can be
|
|
* downloaded from http://www.adobe.com/devnet/swf.html.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <zlib.h>
|
|
|
|
#include "avcodec.h"
|
|
#include "get_bits.h"
|
|
|
|
typedef struct FlashSVContext {
|
|
AVCodecContext *avctx;
|
|
AVFrame frame;
|
|
int image_width, image_height;
|
|
int block_width, block_height;
|
|
uint8_t *tmpblock;
|
|
int block_size;
|
|
z_stream zstream;
|
|
} FlashSVContext;
|
|
|
|
|
|
static void copy_region(uint8_t *sptr, uint8_t *dptr,
|
|
int dx, int dy, int h, int w, int stride)
|
|
{
|
|
int i;
|
|
|
|
for (i = dx + h; i > dx; i--) {
|
|
memcpy(dptr + i * stride + dy * 3, sptr, w * 3);
|
|
sptr += w * 3;
|
|
}
|
|
}
|
|
|
|
|
|
static av_cold int flashsv_decode_init(AVCodecContext *avctx)
|
|
{
|
|
FlashSVContext *s = avctx->priv_data;
|
|
int zret; // Zlib return code
|
|
|
|
s->avctx = avctx;
|
|
s->zstream.zalloc = Z_NULL;
|
|
s->zstream.zfree = Z_NULL;
|
|
s->zstream.opaque = Z_NULL;
|
|
zret = inflateInit(&s->zstream);
|
|
if (zret != Z_OK) {
|
|
av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
|
|
return 1;
|
|
}
|
|
avctx->pix_fmt = PIX_FMT_BGR24;
|
|
s->frame.data[0] = NULL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int flashsv_decode_frame(AVCodecContext *avctx, void *data,
|
|
int *data_size, AVPacket *avpkt)
|
|
{
|
|
int buf_size = avpkt->size;
|
|
FlashSVContext *s = avctx->priv_data;
|
|
int h_blocks, v_blocks, h_part, v_part, i, j;
|
|
GetBitContext gb;
|
|
|
|
/* no supplementary picture */
|
|
if (buf_size == 0)
|
|
return 0;
|
|
if (buf_size < 4)
|
|
return -1;
|
|
|
|
init_get_bits(&gb, avpkt->data, buf_size * 8);
|
|
|
|
/* start to parse the bitstream */
|
|
s->block_width = 16 * (get_bits(&gb, 4) + 1);
|
|
s->image_width = get_bits(&gb, 12);
|
|
s->block_height = 16 * (get_bits(&gb, 4) + 1);
|
|
s->image_height = get_bits(&gb, 12);
|
|
|
|
/* calculate number of blocks and size of border (partial) blocks */
|
|
h_blocks = s->image_width / s->block_width;
|
|
h_part = s->image_width % s->block_width;
|
|
v_blocks = s->image_height / s->block_height;
|
|
v_part = s->image_height % s->block_height;
|
|
|
|
/* the block size could change between frames, make sure the buffer
|
|
* is large enough, if not, get a larger one */
|
|
if (s->block_size < s->block_width * s->block_height) {
|
|
av_free(s->tmpblock);
|
|
if ((s->tmpblock = av_malloc(3 * s->block_width * s->block_height)) == NULL) {
|
|
av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
}
|
|
s->block_size = s->block_width * s->block_height;
|
|
|
|
/* initialize the image size once */
|
|
if (avctx->width == 0 && avctx->height == 0) {
|
|
avctx->width = s->image_width;
|
|
avctx->height = s->image_height;
|
|
}
|
|
|
|
/* check for changes of image width and image height */
|
|
if (avctx->width != s->image_width || avctx->height != s->image_height) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"Frame width or height differs from first frames!\n");
|
|
av_log(avctx, AV_LOG_ERROR, "fh = %d, fv %d vs ch = %d, cv = %d\n",
|
|
avctx->height, avctx->width, s->image_height, s->image_width);
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
av_dlog(avctx, "image: %dx%d block: %dx%d num: %dx%d part: %dx%d\n",
|
|
s->image_width, s->image_height, s->block_width, s->block_height,
|
|
h_blocks, v_blocks, h_part, v_part);
|
|
|
|
s->frame.reference = 3;
|
|
s->frame.buffer_hints = FF_BUFFER_HINTS_VALID |
|
|
FF_BUFFER_HINTS_PRESERVE |
|
|
FF_BUFFER_HINTS_REUSABLE;
|
|
if (avctx->reget_buffer(avctx, &s->frame) < 0) {
|
|
av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
|
|
return -1;
|
|
}
|
|
|
|
/* loop over all block columns */
|
|
for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
|
|
|
|
int y_pos = j * s->block_height; // vertical position in frame
|
|
int cur_blk_height = (j < v_blocks) ? s->block_height : v_part;
|
|
|
|
/* loop over all block rows */
|
|
for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
|
|
int x_pos = i * s->block_width; // horizontal position in frame
|
|
int cur_blk_width = (i < h_blocks) ? s->block_width : h_part;
|
|
|
|
/* get the size of the compressed zlib chunk */
|
|
int size = get_bits(&gb, 16);
|
|
if (8 * size > get_bits_left(&gb)) {
|
|
avctx->release_buffer(avctx, &s->frame);
|
|
s->frame.data[0] = NULL;
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
/* skip unchanged blocks, which have size 0 */
|
|
if (size) {
|
|
/* decompress block */
|
|
int ret = inflateReset(&s->zstream);
|
|
if (ret != Z_OK) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"error in decompression (reset) of block %dx%d\n", i, j);
|
|
/* return -1; */
|
|
}
|
|
s->zstream.next_in = avpkt->data + get_bits_count(&gb) / 8;
|
|
s->zstream.avail_in = size;
|
|
s->zstream.next_out = s->tmpblock;
|
|
s->zstream.avail_out = s->block_size * 3;
|
|
ret = inflate(&s->zstream, Z_FINISH);
|
|
if (ret == Z_DATA_ERROR) {
|
|
av_log(avctx, AV_LOG_ERROR, "Zlib resync occurred\n");
|
|
inflateSync(&s->zstream);
|
|
ret = inflate(&s->zstream, Z_FINISH);
|
|
}
|
|
|
|
if (ret != Z_OK && ret != Z_STREAM_END) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"error in decompression of block %dx%d: %d\n", i, j, ret);
|
|
/* return -1; */
|
|
}
|
|
copy_region(s->tmpblock, s->frame.data[0],
|
|
s->image_height - (y_pos + cur_blk_height + 1),
|
|
x_pos, cur_blk_height, cur_blk_width,
|
|
s->frame.linesize[0]);
|
|
skip_bits_long(&gb, 8 * size); /* skip the consumed bits */
|
|
}
|
|
}
|
|
}
|
|
|
|
*data_size = sizeof(AVFrame);
|
|
*(AVFrame*)data = s->frame;
|
|
|
|
if ((get_bits_count(&gb) / 8) != buf_size)
|
|
av_log(avctx, AV_LOG_ERROR, "buffer not fully consumed (%d != %d)\n",
|
|
buf_size, (get_bits_count(&gb) / 8));
|
|
|
|
/* report that the buffer was completely consumed */
|
|
return buf_size;
|
|
}
|
|
|
|
|
|
static av_cold int flashsv_decode_end(AVCodecContext *avctx)
|
|
{
|
|
FlashSVContext *s = avctx->priv_data;
|
|
inflateEnd(&s->zstream);
|
|
/* release the frame if needed */
|
|
if (s->frame.data[0])
|
|
avctx->release_buffer(avctx, &s->frame);
|
|
|
|
/* free the tmpblock */
|
|
av_free(s->tmpblock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
AVCodec ff_flashsv_decoder = {
|
|
.name = "flashsv",
|
|
.type = AVMEDIA_TYPE_VIDEO,
|
|
.id = CODEC_ID_FLASHSV,
|
|
.priv_data_size = sizeof(FlashSVContext),
|
|
.init = flashsv_decode_init,
|
|
.close = flashsv_decode_end,
|
|
.decode = flashsv_decode_frame,
|
|
.capabilities = CODEC_CAP_DR1,
|
|
.pix_fmts = (const enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_NONE},
|
|
.long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
|
|
};
|