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FFmpeg/libavcodec/8bps.c
Andreas Rheinhardt a247ac640d avcodec: Constify AVCodecs
Given that the AVCodec.next pointer has now been removed, most of the
AVCodecs are not modified at all any more and can therefore be made
const (as this patch does); the only exceptions are the very few codecs
for external libraries that have a init_static_data callback.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
2021-04-27 10:43:15 -03:00

186 lines
5.8 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)
* : BGR24 (RGB 24bpp) (can also output it as RGB32)
* : RGB32 (RGB 32bpp, 4th plane is alpha)
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "decode.h"
#include "internal.h"
static const enum AVPixelFormat pixfmt_rgb24[] = {
AV_PIX_FMT_BGR24, AV_PIX_FMT_0RGB32, AV_PIX_FMT_NONE };
typedef struct EightBpsContext {
AVCodecContext *avctx;
unsigned char planes;
unsigned char planemap[4];
uint32_t pal[256];
} EightBpsContext;
static int decode_frame(AVCodecContext *avctx, void *data,
int *got_frame, AVPacket *avpkt)
{
AVFrame *frame = data;
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
EightBpsContext * const c = avctx->priv_data;
const unsigned char *encoded = buf;
unsigned char *pixptr, *pixptr_end;
unsigned int height = avctx->height; // Real image height
unsigned int dlen, p, row;
const unsigned char *lp, *dp, *ep;
unsigned char count;
unsigned int px_inc;
unsigned int planes = c->planes;
unsigned char *planemap = c->planemap;
int ret;
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);
px_inc = planes + (avctx->pix_fmt == AV_PIX_FMT_0RGB32);
for (p = 0; p < planes; p++) {
/* Lines length pointer for this plane */
lp = encoded + p * (height << 1);
/* Decode a plane */
for (row = 0; row < height; row++) {
pixptr = frame->data[0] + row * frame->linesize[0] + planemap[p];
pixptr_end = pixptr + frame->linesize[0];
if (ep - lp < row * 2 + 2)
return AVERROR_INVALIDDATA;
dlen = av_be2ne16(*(const unsigned short *)(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 * px_inc)
break;
if (ep - dp < count)
return AVERROR_INVALIDDATA;
while (count--) {
*pixptr = *dp++;
pixptr += px_inc;
}
} else {
count = 257 - count;
if (pixptr_end - pixptr < count * px_inc)
break;
while (count--) {
*pixptr = *dp;
pixptr += px_inc;
}
dp++;
dlen -= 2;
}
}
}
}
if (avctx->bits_per_coded_sample <= 8) {
frame->palette_has_changed = ff_copy_palette(c->pal, avpkt, avctx);
memcpy (frame->data[1], c->pal, AVPALETTE_SIZE);
}
*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 = ff_get_format(avctx, pixfmt_rgb24);
c->planes = 3;
c->planemap[0] = 2; // 1st plane is red
c->planemap[1] = 1; // 2nd plane is green
c->planemap[2] = 0; // 3rd plane is blue
break;
case 32:
avctx->pix_fmt = AV_PIX_FMT_RGB32;
c->planes = 4;
/* handle planemap setup later for decoding rgb24 data as rbg32 */
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_RGB32) {
c->planemap[0] = HAVE_BIGENDIAN ? 1 : 2; // 1st plane is red
c->planemap[1] = HAVE_BIGENDIAN ? 2 : 1; // 2nd plane is green
c->planemap[2] = HAVE_BIGENDIAN ? 3 : 0; // 3rd plane is blue
c->planemap[3] = HAVE_BIGENDIAN ? 0 : 3; // 4th plane is alpha
}
return 0;
}
const AVCodec ff_eightbps_decoder = {
.name = "8bps",
.long_name = NULL_IF_CONFIG_SMALL("QuickTime 8BPS video"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_8BPS,
.priv_data_size = sizeof(EightBpsContext),
.init = decode_init,
.decode = decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};