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/*
* YUV4MPEG demuxer
* Copyright (c) 2001, 2002, 2003 Fabrice Bellard
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include "internal.h"
#include "yuv4mpeg.h"
/* Header size increased to allow room for optional flags */
#define MAX_YUV4_HEADER 80
#define MAX_FRAME_HEADER 80
static int yuv4_read_header(AVFormatContext *s)
{
char header[MAX_YUV4_HEADER + 10]; // Include headroom for
// the longest option
char *tokstart, *tokend, *header_end;
int i;
AVIOContext *pb = s->pb;
int width = -1, height = -1, raten = 0,
rated = 0, aspectn = 0, aspectd = 0;
enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE, alt_pix_fmt = AV_PIX_FMT_NONE;
enum AVChromaLocation chroma_sample_location = AVCHROMA_LOC_UNSPECIFIED;
enum AVFieldOrder field_order = AV_FIELD_UNKNOWN;
AVStream *st;
for (i = 0; i < MAX_YUV4_HEADER; i++) {
header[i] = avio_r8(pb);
if (header[i] == '\n') {
header[i + 1] = 0x20; // Add a space after last option.
// Makes parsing "444" vs "444alpha" easier.
header[i + 2] = 0;
break;
}
}
if (i == MAX_YUV4_HEADER)
return -1;
if (strncmp(header, Y4M_MAGIC, strlen(Y4M_MAGIC)))
return -1;
header_end = &header[i + 1]; // Include space
for (tokstart = &header[strlen(Y4M_MAGIC) + 1];
tokstart < header_end; tokstart++) {
if (*tokstart == 0x20)
continue;
switch (*tokstart++) {
case 'W': // Width. Required.
width = strtol(tokstart, &tokend, 10);
tokstart = tokend;
break;
case 'H': // Height. Required.
height = strtol(tokstart, &tokend, 10);
tokstart = tokend;
break;
case 'C': // Color space
if (strncmp("420jpeg", tokstart, 7) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P;
chroma_sample_location = AVCHROMA_LOC_CENTER;
} else if (strncmp("420mpeg2", tokstart, 8) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P;
chroma_sample_location = AVCHROMA_LOC_LEFT;
} else if (strncmp("420paldv", tokstart, 8) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P;
chroma_sample_location = AVCHROMA_LOC_TOPLEFT;
} else if (strncmp("420", tokstart, 3) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P;
chroma_sample_location = AVCHROMA_LOC_CENTER;
} else if (strncmp("411", tokstart, 3) == 0)
pix_fmt = AV_PIX_FMT_YUV411P;
else if (strncmp("422", tokstart, 3) == 0)
pix_fmt = AV_PIX_FMT_YUV422P;
else if (strncmp("444alpha", tokstart, 8) == 0 ) {
av_log(s, AV_LOG_ERROR, "Cannot handle 4:4:4:4 "
"YUV4MPEG stream.\n");
return -1;
} else if (strncmp("444", tokstart, 3) == 0)
pix_fmt = AV_PIX_FMT_YUV444P;
else if (strncmp("mono", tokstart, 4) == 0) {
pix_fmt = AV_PIX_FMT_GRAY8;
} else {
av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains an unknown "
"pixel format.\n");
return -1;
}
while (tokstart < header_end && *tokstart != 0x20)
tokstart++;
break;
case 'I': // Interlace type
switch (*tokstart++){
case '?':
field_order = AV_FIELD_UNKNOWN;
break;
case 'p':
field_order = AV_FIELD_PROGRESSIVE;
break;
case 't':
field_order = AV_FIELD_TT;
break;
case 'b':
field_order = AV_FIELD_BB;
break;
case 'm':
av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains mixed "
"interlaced and non-interlaced frames.\n");
return -1;
default:
av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
return -1;
}
break;
case 'F': // Frame rate
sscanf(tokstart, "%d:%d", &raten, &rated); // 0:0 if unknown
while (tokstart < header_end && *tokstart != 0x20)
tokstart++;
break;
case 'A': // Pixel aspect
sscanf(tokstart, "%d:%d", &aspectn, &aspectd); // 0:0 if unknown
while (tokstart < header_end && *tokstart != 0x20)
tokstart++;
break;
case 'X': // Vendor extensions
if (strncmp("YSCSS=", tokstart, 6) == 0) {
// Older nonstandard pixel format representation
tokstart += 6;
if (strncmp("420JPEG", tokstart, 7) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P;
else if (strncmp("420MPEG2", tokstart, 8) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P;
else if (strncmp("420PALDV", tokstart, 8) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P;
else if (strncmp("411", tokstart, 3) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV411P;
else if (strncmp("422", tokstart, 3) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV422P;
else if (strncmp("444", tokstart, 3) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV444P;
}
while (tokstart < header_end && *tokstart != 0x20)
tokstart++;
break;
}
}
if (width == -1 || height == -1) {
av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
return -1;
}
if (pix_fmt == AV_PIX_FMT_NONE) {
if (alt_pix_fmt == AV_PIX_FMT_NONE)
pix_fmt = AV_PIX_FMT_YUV420P;
else
pix_fmt = alt_pix_fmt;
}
if (raten <= 0 || rated <= 0) {
// Frame rate unknown
raten = 25;
rated = 1;
}
if (aspectn == 0 && aspectd == 0) {
// Pixel aspect unknown
aspectd = 1;
}
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->width = width;
st->codec->height = height;
av_reduce(&raten, &rated, raten, rated, (1UL << 31) - 1);
avpriv_set_pts_info(st, 64, rated, raten);
st->avg_frame_rate = av_inv_q(st->time_base);
st->codec->pix_fmt = pix_fmt;
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = AV_CODEC_ID_RAWVIDEO;
st->sample_aspect_ratio = (AVRational){ aspectn, aspectd };
st->codec->chroma_sample_location = chroma_sample_location;
st->codec->field_order = field_order;
return 0;
}
static int yuv4_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int i;
char header[MAX_FRAME_HEADER+1];
int packet_size, width, height, ret;
AVStream *st = s->streams[0];
for (i = 0; i < MAX_FRAME_HEADER; i++) {
header[i] = avio_r8(s->pb);
if (header[i] == '\n') {
header[i + 1] = 0;
break;
}
}
if (s->pb->error)
return s->pb->error;
else if (s->pb->eof_reached)
return AVERROR_EOF;
else if (i == MAX_FRAME_HEADER)
return AVERROR_INVALIDDATA;
if (strncmp(header, Y4M_FRAME_MAGIC, strlen(Y4M_FRAME_MAGIC)))
return AVERROR_INVALIDDATA;
width = st->codec->width;
height = st->codec->height;
packet_size = avpicture_get_size(st->codec->pix_fmt, width, height);
if (packet_size < 0)
return packet_size;
ret = av_get_packet(s->pb, pkt, packet_size);
if (ret < 0)
return ret;
else if (ret != packet_size)
return s->pb->eof_reached ? AVERROR_EOF : AVERROR(EIO);
pkt->stream_index = 0;
return 0;
}
static int yuv4_probe(AVProbeData *pd)
{
/* check file header */
if (strncmp(pd->buf, Y4M_MAGIC, sizeof(Y4M_MAGIC) - 1) == 0)
return AVPROBE_SCORE_MAX;
else
return 0;
}
AVInputFormat ff_yuv4mpegpipe_demuxer = {
.name = "yuv4mpegpipe",
.long_name = NULL_IF_CONFIG_SMALL("YUV4MPEG pipe"),
.read_probe = yuv4_probe,
.read_header = yuv4_read_header,
.read_packet = yuv4_read_packet,
.extensions = "y4m",
};
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