* Copyright (C) 2004 Alex Beregszaszi
* Copyright (C) 2006 Benjamin Larsson
*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * 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.
*
- * FFmpeg is distributed in the hope that it will be useful,
+ * 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 FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file libavcodec/flashsv.c
+ * @file
* Flash Screen Video decoder
* @author Alex Beregszaszi
* @author Benjamin Larsson
- */
-
-/* Bitstream description
- * The picture is divided into blocks that are zlib compressed.
- *
- * The decoder is fed complete frames, the frameheader contains:
- * 4bits of block width
- * 12bits of frame width
- * 4bits of block height
- * 12bits of frame height
- *
- * Directly after the header are the compressed blocks. The blocks
- * have their compressed size represented with 16bits in the beginnig.
- * If the size = 0 then the block is unchanged from the previous frame.
- * All blocks are decompressed until the buffer is consumed.
*
- * Encoding ideas, a basic encoder would just use a fixed block size.
- * Block sizes can be multipels of 16, from 16 to 256. The blocks don't
- * have to be quadratic. A brute force search with a set of diffrent
- * block sizes should give a better result then to just use a fixed size.
+ * 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 "bitstream.h"
-
-#include <zlib.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;
+ 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->avctx = avctx;
s->zstream.zalloc = Z_NULL;
- s->zstream.zfree = Z_NULL;
+ s->zstream.zfree = Z_NULL;
s->zstream.opaque = Z_NULL;
- zret = inflateInit(&(s->zstream));
+ zret = inflateInit(&s->zstream);
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
return 1;
}
-static int flashsv_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- AVPacket *avpkt)
+static int flashsv_decode_block(AVCodecContext *avctx, AVPacket *avpkt,
+ GetBitContext *gb, int block_size,
+ int width, int height, int x_pos, int y_pos)
{
- const uint8_t *buf = avpkt->data;
- int buf_size = avpkt->size;
- FlashSVContext *s = avctx->priv_data;
+ struct FlashSVContext *s = avctx->priv_data;
+ uint8_t *line = s->tmpblock;
+ int k;
+ int ret = inflateReset(&s->zstream);
+ if (ret != Z_OK) {
+ //return -1;
+ }
+ s->zstream.next_in = avpkt->data + get_bits_count(gb) / 8;
+ s->zstream.avail_in = block_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) {
+ //return -1;
+ }
+ /* Flash Screen Video stores the image upside down, so copy
+ * lines to destination in reverse order. */
+ for (k = 1; k <= height; k++) {
+ memcpy(s->frame.data[0] + x_pos * 3 +
+ (s->image_height - y_pos - k) * s->frame.linesize[0],
+ line, width * 3);
+ /* advance source pointer to next line */
+ line += width * 3;
+ }
+ skip_bits_long(gb, 8 * block_size); /* skip the consumed bits */
+ 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;
- if(s->frame.data[0])
- avctx->release_buffer(avctx, &s->frame);
-
- init_get_bits(&gb, buf, buf_size * 8);
+ 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 amount of blocks and the size of the border blocks */
- h_blocks = s->image_width / s->block_width;
- h_part = s->image_width % s->block_width;
+ 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;
+ 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) {
- if (s->tmpblock != NULL)
- av_free(s->tmpblock);
- if ((s->tmpblock = av_malloc(3*s->block_width*s->block_height)) == NULL) {
+ 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 -1;
+ return AVERROR(ENOMEM);
}
}
- s->block_size = s->block_width*s->block_height;
+ s->block_size = s->block_width * s->block_height;
- /* init the image size once */
- if((avctx->width==0) && (avctx->height==0)){
- avctx->width = s->image_width;
+ /* 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 -1;
+ 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_log(avctx, AV_LOG_DEBUG, "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);
+ 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 = 1;
- s->frame.buffer_hints = FF_BUFFER_HINTS_VALID;
- if (avctx->get_buffer(avctx, &s->frame) < 0) {
- av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ 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 hp = j*s->block_height; // horiz position in frame
- int hs = (j<v_blocks)?s->block_height:v_part; // size of block
+ 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 wp = i*s->block_width; // vert position in frame
- int ws = (i<h_blocks)?s->block_width:h_part; // size of block
+ 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;
+ }
- if (size == 0) {
- /* no change, don't do anything */
- } else {
- /* 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 = buf+(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-(hp+hs+1), wp, hs, ws, s->frame.linesize[0]);
- skip_bits_long(&gb, 8*size); /* skip the consumed bits */
+ /* skip unchanged blocks, which have size 0 */
+ if (size) {
+ if (flashsv_decode_block(avctx, avpkt, &gb, size,
+ cur_blk_width, cur_blk_height,
+ x_pos, y_pos))
+ av_log(avctx, AV_LOG_ERROR,
+ "error in decompression of block %dx%d\n", i, j);
}
}
}
*data_size = sizeof(AVFrame);
*(AVFrame*)data = s->frame;
- if ((get_bits_count(&gb)/8) != buf_size)
+ 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));
+ 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));
+ inflateEnd(&s->zstream);
/* release the frame if needed */
if (s->frame.data[0])
avctx->release_buffer(avctx, &s->frame);
/* free the tmpblock */
- if (s->tmpblock != NULL)
- av_free(s->tmpblock);
+ av_free(s->tmpblock);
return 0;
}
-AVCodec flashsv_decoder = {
- "flashsv",
- CODEC_TYPE_VIDEO,
- CODEC_ID_FLASHSV,
- sizeof(FlashSVContext),
- flashsv_decode_init,
- NULL,
- flashsv_decode_end,
- flashsv_decode_frame,
- CODEC_CAP_DR1,
- .pix_fmts = (enum PixelFormat[]){PIX_FMT_BGR24, PIX_FMT_NONE},
- .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video v1"),
+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"),
};
projects / ffmpeg / blobdiff