ffmpeg/libavcodec/8bps.c

179 lines
5.4 KiB
C

/*
* Quicktime Planar RGB (8BPS) Video Decoder
* Copyright (C) 2003 Roberto Togni
*
* 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
* QT 8BPS Video Decoder by Roberto Togni
* For more information about the 8BPS format, visit:
* http://www.pcisys.net/~melanson/codecs/
*
* Supports: PAL8 (RGB 8bpp, paletted)
* : GBRP (RGB 24bpp)
* : GBRAP (RGB 32bpp, 4th plane is alpha)
*/
#include <string.h>
#include "libavutil/intreadwrite.h"
#include "libavutil/internal.h"
#include "avcodec.h"
#include "codec_internal.h"
#include "decode.h"
typedef struct EightBpsContext {
AVCodecContext *avctx;
uint8_t planes;
uint8_t planemap[4];
} EightBpsContext;
static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
int *got_frame, AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
EightBpsContext * const c = avctx->priv_data;
const uint8_t *encoded = buf;
uint8_t *pixptr, *pixptr_end;
unsigned int height = avctx->height; // Real image height
unsigned int dlen, p, row;
const uint8_t *lp, *dp, *ep;
uint8_t count;
const uint8_t *planemap = c->planemap;
unsigned int planes = c->planes;
int ret;
if (buf_size < planes * height * 2)
return AVERROR_INVALIDDATA;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
ep = encoded + buf_size;
/* Set data pointer after line lengths */
dp = encoded + planes * (height << 1);
for (p = 0; p < planes; p++) {
const int pi = planemap[p];
/* Lines length pointer for this plane */
lp = encoded + p * (height << 1);
/* Decode a plane */
for (row = 0; row < height; row++) {
pixptr = frame->data[pi] + row * frame->linesize[pi];
pixptr_end = pixptr + frame->linesize[pi];
if (ep - lp < row * 2 + 2)
return AVERROR_INVALIDDATA;
dlen = AV_RB16(lp + row * 2);
/* Decode a row of this plane */
while (dlen > 0) {
if (ep - dp <= 1)
return AVERROR_INVALIDDATA;
if ((count = *dp++) <= 127) {
count++;
dlen -= count + 1;
if (pixptr_end - pixptr < count)
break;
if (ep - dp < count)
return AVERROR_INVALIDDATA;
memcpy(pixptr, dp, count);
pixptr += count;
dp += count;
} else {
count = 257 - count;
if (pixptr_end - pixptr < count)
break;
memset(pixptr, dp[0], count);
pixptr += count;
dp++;
dlen -= 2;
}
}
}
}
if (avctx->bits_per_coded_sample <= 8) {
#if FF_API_PALETTE_HAS_CHANGED
FF_DISABLE_DEPRECATION_WARNINGS
frame->palette_has_changed =
#endif
ff_copy_palette(frame->data[1], avpkt, avctx);
#if FF_API_PALETTE_HAS_CHANGED
FF_ENABLE_DEPRECATION_WARNINGS
#endif
}
*got_frame = 1;
/* always report that the buffer was completely consumed */
return buf_size;
}
static av_cold int decode_init(AVCodecContext *avctx)
{
EightBpsContext * const c = avctx->priv_data;
c->avctx = avctx;
switch (avctx->bits_per_coded_sample) {
case 8:
avctx->pix_fmt = AV_PIX_FMT_PAL8;
c->planes = 1;
c->planemap[0] = 0; // 1st plane is palette indexes
break;
case 24:
avctx->pix_fmt = AV_PIX_FMT_GBRP;
c->planes = 3;
c->planemap[0] = 2; // 1st plane is red
c->planemap[1] = 0; // 2nd plane is green
c->planemap[2] = 1; // 3rd plane is blue
break;
case 32:
avctx->pix_fmt = AV_PIX_FMT_GBRAP;
c->planes = 4;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Error: Unsupported color depth: %u.\n",
avctx->bits_per_coded_sample);
return AVERROR_INVALIDDATA;
}
if (avctx->pix_fmt == AV_PIX_FMT_GBRAP) {
c->planemap[0] = 2; // 1st plane is red
c->planemap[1] = 0; // 2nd plane is green
c->planemap[2] = 1; // 3rd plane is blue
c->planemap[3] = 3; // 4th plane is alpha
}
return 0;
}
const FFCodec ff_eightbps_decoder = {
.p.name = "8bps",
CODEC_LONG_NAME("QuickTime 8BPS video"),
.p.type = AVMEDIA_TYPE_VIDEO,
.p.id = AV_CODEC_ID_8BPS,
.priv_data_size = sizeof(EightBpsContext),
.init = decode_init,
FF_CODEC_DECODE_CB(decode_frame),
.p.capabilities = AV_CODEC_CAP_DR1,
};