FFmpeg/libavcodec/aasc.c
James Almer 9ea6d2149e avcodec/decode: add a flags parameter to ff_reget_buffer()
Some decoders may not need a writable buffer in some specific cases, but only
a reference to the existing buffer with updated frame properties instead, for
the purpose of returning duplicate frames. For this, the
FF_REGET_BUFFER_FLAG_READONLY flag is added, which will prevent potential
allocations and buffer copies when they are not needed.

Signed-off-by: James Almer <jamrial@gmail.com>
2019-09-04 10:07:12 -03:00

164 lines
4.5 KiB
C

/*
* Autodesk RLE Decoder
* Copyright (C) 2005 The FFmpeg project
*
* 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
* Autodesk RLE Video Decoder by Konstantin Shishkov
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "avcodec.h"
#include "internal.h"
#include "msrledec.h"
typedef struct AascContext {
AVCodecContext *avctx;
GetByteContext gb;
AVFrame *frame;
uint32_t palette[AVPALETTE_COUNT];
int palette_size;
} AascContext;
static av_cold int aasc_decode_init(AVCodecContext *avctx)
{
AascContext *s = avctx->priv_data;
uint8_t *ptr;
int i;
s->avctx = avctx;
switch (avctx->bits_per_coded_sample) {
case 8:
avctx->pix_fmt = AV_PIX_FMT_PAL8;
ptr = avctx->extradata;
s->palette_size = FFMIN(avctx->extradata_size, AVPALETTE_SIZE);
for (i = 0; i < s->palette_size / 4; i++) {
s->palette[i] = 0xFFU << 24 | AV_RL32(ptr);
ptr += 4;
}
break;
case 16:
avctx->pix_fmt = AV_PIX_FMT_RGB555LE;
break;
case 24:
avctx->pix_fmt = AV_PIX_FMT_BGR24;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unsupported bit depth: %d\n", avctx->bits_per_coded_sample);
return -1;
}
s->frame = av_frame_alloc();
if (!s->frame)
return AVERROR(ENOMEM);
return 0;
}
static int aasc_decode_frame(AVCodecContext *avctx,
void *data, int *got_frame,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
AascContext *s = avctx->priv_data;
int compr, i, stride, psize, ret;
if (buf_size < 4) {
av_log(avctx, AV_LOG_ERROR, "frame too short\n");
return AVERROR_INVALIDDATA;
}
if ((ret = ff_reget_buffer(avctx, s->frame, 0)) < 0)
return ret;
compr = AV_RL32(buf);
buf += 4;
buf_size -= 4;
psize = avctx->bits_per_coded_sample / 8;
switch (avctx->codec_tag) {
case MKTAG('A', 'A', 'S', '4'):
bytestream2_init(&s->gb, buf - 4, buf_size + 4);
ff_msrle_decode(avctx, s->frame, 8, &s->gb);
break;
case MKTAG('A', 'A', 'S', 'C'):
switch (compr) {
case 0:
stride = (avctx->width * psize + psize) & ~psize;
if (buf_size < stride * avctx->height)
return AVERROR_INVALIDDATA;
for (i = avctx->height - 1; i >= 0; i--) {
memcpy(s->frame->data[0] + i * s->frame->linesize[0], buf, avctx->width * psize);
buf += stride;
buf_size -= stride;
}
break;
case 1:
bytestream2_init(&s->gb, buf, buf_size);
ff_msrle_decode(avctx, s->frame, 8, &s->gb);
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown compression type %d\n", compr);
return AVERROR_INVALIDDATA;
}
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown FourCC: %X\n", avctx->codec_tag);
return -1;
}
if (avctx->pix_fmt == AV_PIX_FMT_PAL8)
memcpy(s->frame->data[1], s->palette, s->palette_size);
*got_frame = 1;
if ((ret = av_frame_ref(data, s->frame)) < 0)
return ret;
/* report that the buffer was completely consumed */
return avpkt->size;
}
static av_cold int aasc_decode_end(AVCodecContext *avctx)
{
AascContext *s = avctx->priv_data;
av_frame_free(&s->frame);
return 0;
}
AVCodec ff_aasc_decoder = {
.name = "aasc",
.long_name = NULL_IF_CONFIG_SMALL("Autodesk RLE"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_AASC,
.priv_data_size = sizeof(AascContext),
.init = aasc_decode_init,
.close = aasc_decode_end,
.decode = aasc_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE,
};