ffmpeg/libavcodec/tscc.c

186 lines
5.4 KiB
C

/*
* TechSmith Camtasia decoder
* Copyright (c) 2004 Konstantin Shishkov
*
* This file is part of FFmpeg.
*
* FFmpeg 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,
* 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
* 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 "libavutil/mem.h"
#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
#include "msrledec.h"
#include "zlib_wrapper.h"
#include <zlib.h>
typedef struct TsccContext {
AVCodecContext *avctx;
AVFrame *frame;
// Bits per pixel
int bpp;
// Decompressed data size
unsigned int decomp_size;
// Decompression buffer
unsigned char* decomp_buf;
GetByteContext gb;
int height;
FFZStream zstream;
uint32_t pal[256];
} CamtasiaContext;
static int decode_frame(AVCodecContext *avctx, AVFrame *rframe,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
CamtasiaContext * const c = avctx->priv_data;
z_stream *const zstream = &c->zstream.zstream;
AVFrame *frame = c->frame;
int ret;
int palette_has_changed = 0;
if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
palette_has_changed = ff_copy_palette(c->pal, avpkt, avctx);
}
ret = inflateReset(zstream);
if (ret != Z_OK) {
av_log(avctx, AV_LOG_ERROR, "Inflate reset error: %d\n", ret);
return AVERROR_UNKNOWN;
}
zstream->next_in = buf;
zstream->avail_in = buf_size;
zstream->next_out = c->decomp_buf;
zstream->avail_out = c->decomp_size;
ret = inflate(zstream, Z_FINISH);
// Z_DATA_ERROR means empty picture
if (ret == Z_DATA_ERROR && !palette_has_changed) {
return buf_size;
}
if ((ret != Z_OK) && (ret != Z_STREAM_END) && (ret != Z_DATA_ERROR)) {
av_log(avctx, AV_LOG_ERROR, "Inflate error: %d\n", ret);
return AVERROR_UNKNOWN;
}
if ((ret = ff_reget_buffer(avctx, frame, 0)) < 0)
return ret;
if (ret != Z_DATA_ERROR) {
bytestream2_init(&c->gb, c->decomp_buf,
c->decomp_size - zstream->avail_out);
ff_msrle_decode(avctx, frame, c->bpp, &c->gb);
}
/* make the palette available on the way out */
if (c->avctx->pix_fmt == AV_PIX_FMT_PAL8) {
#if FF_API_PALETTE_HAS_CHANGED
FF_DISABLE_DEPRECATION_WARNINGS
frame->palette_has_changed = palette_has_changed;
FF_ENABLE_DEPRECATION_WARNINGS
#endif
memcpy(frame->data[1], c->pal, AVPALETTE_SIZE);
}
if ((ret = av_frame_ref(rframe, frame)) < 0)
return ret;
*got_frame = 1;
/* always report that the buffer was completely consumed */
return buf_size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
CamtasiaContext * const c = avctx->priv_data;
c->avctx = avctx;
c->height = avctx->height;
switch(avctx->bits_per_coded_sample){
case 8: avctx->pix_fmt = AV_PIX_FMT_PAL8; break;
case 16: avctx->pix_fmt = AV_PIX_FMT_RGB555; break;
case 24:
avctx->pix_fmt = AV_PIX_FMT_BGR24;
break;
case 32: avctx->pix_fmt = AV_PIX_FMT_0RGB32; break;
default: av_log(avctx, AV_LOG_ERROR, "Camtasia error: unknown depth %i bpp\n", avctx->bits_per_coded_sample);
return AVERROR_PATCHWELCOME;
}
c->bpp = avctx->bits_per_coded_sample;
// buffer size for RLE 'best' case when 2-byte code precedes 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))) {
av_log(avctx, AV_LOG_ERROR, "Can't allocate decompression buffer.\n");
return AVERROR(ENOMEM);
}
}
c->frame = av_frame_alloc();
if (!c->frame)
return AVERROR(ENOMEM);
return ff_inflate_init(&c->zstream, avctx);
}
static av_cold int decode_end(AVCodecContext *avctx)
{
CamtasiaContext * const c = avctx->priv_data;
av_freep(&c->decomp_buf);
av_frame_free(&c->frame);
ff_inflate_end(&c->zstream);
return 0;
}
const FFCodec ff_tscc_decoder = {
.p.name = "camtasia",
CODEC_LONG_NAME("TechSmith Screen Capture Codec"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_TSCC,
.priv_data_size = sizeof(CamtasiaContext),
.init = decode_init,
.close = decode_end,
FF_CODEC_DECODE_CB(decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_CLEANUP,
};