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/*
* TechSmith Camtasia decoder
* Copyright (c) 2004 Konstantin Shishkov
*
* 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
* TechSmith Camtasia decoder
*
* Fourcc: TSCC
*
* Codec is very simple:
* it codes picture (picture difference, really)
* with algorithm almost identical to Windows RLE8,
* only without padding and with greater pixel sizes,
* then this coded picture is packed with ZLib
*
* Supports: BGR8,BGR555,BGR24 - only BGR8 and BGR555 tested
*
*/
#include <stdio.h>
#include <stdlib.h>
#include "avcodec.h"
#include "msrledec.h"
#include <zlib.h>
/*
* Decoder context
*/
typedef struct TsccContext {
AVCodecContext *avctx;
AVFrame pic;
// Bits per pixel
int bpp;
// Decompressed data size
unsigned int decomp_size;
// Decompression buffer
unsigned char* decomp_buf;
int height;
z_stream zstream;
} CamtasiaContext;
/*
*
* Decode a frame
*
*/
static int decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
CamtasiaContext * const c = avctx->priv_data;
const unsigned char *encoded = buf;
unsigned char *outptr;
int zret; // Zlib return code
int len = buf_size;
if(c->pic.data[0])
avctx->release_buffer(avctx, &c->pic);
c->pic.reference = 1;
c->pic.buffer_hints = FF_BUFFER_HINTS_VALID;
if(avctx->get_buffer(avctx, &c->pic) < 0){
av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
return -1;
}
outptr = c->pic.data[0]; // Output image pointer
zret = inflateReset(&(c->zstream));
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", zret);
return -1;
}
c->zstream.next_in = encoded;
c->zstream.avail_in = len;
c->zstream.next_out = c->decomp_buf;
c->zstream.avail_out = c->decomp_size;
zret = inflate(&(c->zstream), Z_FINISH);
// Z_DATA_ERROR means empty picture
if ((zret != Z_OK) && (zret != Z_STREAM_END) && (zret != Z_DATA_ERROR)) {
av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", zret);
return -1;
}
if(zret != Z_DATA_ERROR)
ff_msrle_decode(avctx, (AVPicture*)&c->pic, c->bpp, c->decomp_buf, c->decomp_size - c->zstream.avail_out);
/* make the palette available on the way out */
if (c->avctx->pix_fmt == PIX_FMT_PAL8) {
memcpy(c->pic.data[1], c->avctx->palctrl->palette, AVPALETTE_SIZE);
if (c->avctx->palctrl->palette_changed) {
c->pic.palette_has_changed = 1;
c->avctx->palctrl->palette_changed = 0;
}
}
*data_size = sizeof(AVFrame);
*(AVFrame*)data = c->pic;
/* always report that the buffer was completely consumed */
return buf_size;
}
/*
*
* Init tscc decoder
*
*/
static av_cold int decode_init(AVCodecContext *avctx)
{
CamtasiaContext * const c = avctx->priv_data;
int zret; // Zlib return code
c->avctx = avctx;
c->height = avctx->height;
// Needed if zlib unused or init aborted before inflateInit
memset(&(c->zstream), 0, sizeof(z_stream));
switch(avctx->bits_per_coded_sample){
case 8: avctx->pix_fmt = PIX_FMT_PAL8; break;
case 16: avctx->pix_fmt = PIX_FMT_RGB555; break;
case 24:
avctx->pix_fmt = PIX_FMT_BGR24;
break;
case 32: avctx->pix_fmt = PIX_FMT_RGB32; break;
default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
return -1;
}
c->bpp = avctx->bits_per_coded_sample;
// buffer size for RLE 'best' case when 2-byte code preceeds each pixel and there may be padding after it too
c->decomp_size = (((avctx->width * c->bpp + 7) >> 3) + 3 * avctx->width + 2) * avctx->height + 2;
/* Allocate decompression buffer */
if (c->decomp_size) {
if ((c->decomp_buf = av_malloc(c->decomp_size)) == NULL) {
av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
return 1;
}
}
c->zstream.zalloc = Z_NULL;
c->zstream.zfree = Z_NULL;
c->zstream.opaque = Z_NULL;
zret = inflateInit(&(c->zstream));
if (zret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate init error: %d\n", zret);
return 1;
}
return 0;
}
/*
*
* Uninit tscc decoder
*
*/
static av_cold int decode_end(AVCodecContext *avctx)
{
CamtasiaContext * const c = avctx->priv_data;
av_freep(&c->decomp_buf);
if (c->pic.data[0])
avctx->release_buffer(avctx, &c->pic);
inflateEnd(&(c->zstream));
return 0;
}
AVCodec ff_tscc_decoder = {
"camtasia",
AVMEDIA_TYPE_VIDEO,
CODEC_ID_TSCC,
sizeof(CamtasiaContext),
decode_init,
NULL,
decode_end,
decode_frame,
CODEC_CAP_DR1,
.long_name = NULL_IF_CONFIG_SMALL("TechSmith Screen Capture Codec"),
};
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