FFmpeg/libavcodec/m101.c
2016-12-03 15:40:26 +01:00

117 lines
4.1 KiB
C

/*
* Copyright (c) 2016 Michael Niedermayer
*
* 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
*/
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
#include "internal.h"
static av_cold int m101_decode_init(AVCodecContext *avctx)
{
if (avctx->extradata_size < 6*4) {
avpriv_request_sample(avctx, "Missing or too small extradata (size %d)", avctx->extradata_size);
return AVERROR_INVALIDDATA;
}
if (avctx->extradata[2*4] == 10)
avctx->pix_fmt = AV_PIX_FMT_YUV422P10;
else if (avctx->extradata[2*4] == 8) {
avctx->pix_fmt = AV_PIX_FMT_YUYV422;
} else {
avpriv_request_sample(avctx, "BPS %d", avctx->extradata[2*4]);
return AVERROR_INVALIDDATA;
}
return 0;
}
static int m101_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int stride, ret;
int x, y;
int min_stride = 2 * avctx->width;
int bits = avctx->extradata[2*4];
AVFrame *frame = data;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
frame->pict_type = AV_PICTURE_TYPE_I;
frame->key_frame = 1;
stride = AV_RL32(avctx->extradata + 5*4);
if (avctx->pix_fmt == AV_PIX_FMT_YUV422P10)
min_stride = (avctx->width + 15) / 16 * 20;
if (stride < min_stride || avpkt->size < stride * (uint64_t)avctx->height) {
av_log(avctx, AV_LOG_ERROR, "stride (%d) is invalid for packet sized %d\n",
stride, avpkt->size);
return AVERROR_INVALIDDATA;
}
frame->interlaced_frame = ((avctx->extradata[3*4] & 3) != 3);
if (frame->interlaced_frame)
frame->top_field_first = avctx->extradata[3*4] & 1;
for (y = 0; y < avctx->height; y++) {
int src_y = y;
if (frame->interlaced_frame)
src_y = ((y&1)^frame->top_field_first) ? y/2 : (y/2 + avctx->height/2);
if (bits == 8) {
uint8_t *line = frame->data[0] + y*frame->linesize[0];
memcpy(line, buf + src_y*stride, 2*avctx->width);
} else {
int block;
uint16_t *luma = (uint16_t*)&frame->data[0][y*frame->linesize[0]];
uint16_t *cb = (uint16_t*)&frame->data[1][y*frame->linesize[1]];
uint16_t *cr = (uint16_t*)&frame->data[2][y*frame->linesize[2]];
for (block = 0; 16*block < avctx->width; block ++) {
const uint8_t *buf_src = buf + src_y*stride + 40*block;
for (x = 0; x < 16 && x + 16*block < avctx->width; x++) {
int xd = x + 16*block;
if (x&1) {
luma [xd] = (4*buf_src[2*x + 0]) + ((buf_src[32 + (x>>1)]>>4)&3);
} else {
luma [xd] = (4*buf_src[2*x + 0]) + (buf_src[32 + (x>>1)] &3);
cb[xd>>1] = (4*buf_src[2*x + 1]) + ((buf_src[32 + (x>>1)]>>2)&3);
cr[xd>>1] = (4*buf_src[2*x + 3]) + (buf_src[32 + (x>>1)]>>6);
}
}
}
}
}
*got_frame = 1;
return avpkt->size;
}
AVCodec ff_m101_decoder = {
.name = "m101",
.long_name = NULL_IF_CONFIG_SMALL("Matrox Uncompressed SD"),
.type = AVMEDIA_TYPE_VIDEO,
.id = AV_CODEC_ID_M101,
.init = m101_decode_init,
.decode = m101_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};