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Regard whitespace Rev 4348 → Rev 4349

/contrib/sdk/sources/ffmpeg/libavformat/yuv4mpeg.c
0,0 → 1,609
/*
* YUV4MPEG format
* Copyright (c) 2001, 2002, 2003 Fabrice Bellard
*
* 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/pixdesc.h"
#include "avformat.h"
#include "internal.h"
 
#define Y4M_MAGIC "YUV4MPEG2"
#define Y4M_FRAME_MAGIC "FRAME"
#define Y4M_LINE_MAX 256
 
#if CONFIG_YUV4MPEGPIPE_MUXER
static int yuv4_generate_header(AVFormatContext *s, char* buf)
{
AVStream *st;
int width, height;
int raten, rated, aspectn, aspectd, n;
char inter;
const char *colorspace = "";
 
st = s->streams[0];
width = st->codec->width;
height = st->codec->height;
 
av_reduce(&raten, &rated, st->codec->time_base.den,
st->codec->time_base.num, (1UL << 31) - 1);
 
aspectn = st->sample_aspect_ratio.num;
aspectd = st->sample_aspect_ratio.den;
 
if (aspectn == 0 && aspectd == 1)
aspectd = 0; // 0:0 means unknown
 
inter = 'p'; /* progressive is the default */
if (st->codec->coded_frame && st->codec->coded_frame->interlaced_frame)
inter = st->codec->coded_frame->top_field_first ? 't' : 'b';
if (st->codec->field_order == AV_FIELD_PROGRESSIVE) {
inter = 'p';
} else if (st->codec->field_order == AV_FIELD_TB || st->codec->field_order == AV_FIELD_TT) {
inter = 't';
} else if (st->codec->field_order == AV_FIELD_BT || st->codec->field_order == AV_FIELD_BB) {
inter = 'b';
}
 
switch (st->codec->pix_fmt) {
case AV_PIX_FMT_GRAY8:
colorspace = " Cmono";
break;
case AV_PIX_FMT_GRAY16:
colorspace = " Cmono16";
break;
case AV_PIX_FMT_YUV411P:
colorspace = " C411 XYSCSS=411";
break;
case AV_PIX_FMT_YUV420P:
switch (st->codec->chroma_sample_location) {
case AVCHROMA_LOC_TOPLEFT: colorspace = " C420paldv XYSCSS=420PALDV"; break;
case AVCHROMA_LOC_LEFT: colorspace = " C420mpeg2 XYSCSS=420MPEG2"; break;
default: colorspace = " C420jpeg XYSCSS=420JPEG"; break;
}
break;
case AV_PIX_FMT_YUV422P:
colorspace = " C422 XYSCSS=422";
break;
case AV_PIX_FMT_YUV444P:
colorspace = " C444 XYSCSS=444";
break;
case AV_PIX_FMT_YUV420P9:
colorspace = " C420p9 XYSCSS=420P9";
break;
case AV_PIX_FMT_YUV422P9:
colorspace = " C422p9 XYSCSS=422P9";
break;
case AV_PIX_FMT_YUV444P9:
colorspace = " C444p9 XYSCSS=444P9";
break;
case AV_PIX_FMT_YUV420P10:
colorspace = " C420p10 XYSCSS=420P10";
break;
case AV_PIX_FMT_YUV422P10:
colorspace = " C422p10 XYSCSS=422P10";
break;
case AV_PIX_FMT_YUV444P10:
colorspace = " C444p10 XYSCSS=444P10";
break;
case AV_PIX_FMT_YUV420P12:
colorspace = " C420p12 XYSCSS=420P12";
break;
case AV_PIX_FMT_YUV422P12:
colorspace = " C422p12 XYSCSS=422P12";
break;
case AV_PIX_FMT_YUV444P12:
colorspace = " C444p12 XYSCSS=444P12";
break;
case AV_PIX_FMT_YUV420P14:
colorspace = " C420p14 XYSCSS=420P14";
break;
case AV_PIX_FMT_YUV422P14:
colorspace = " C422p14 XYSCSS=422P14";
break;
case AV_PIX_FMT_YUV444P14:
colorspace = " C444p14 XYSCSS=444P14";
break;
case AV_PIX_FMT_YUV420P16:
colorspace = " C420p16 XYSCSS=420P16";
break;
case AV_PIX_FMT_YUV422P16:
colorspace = " C422p16 XYSCSS=422P16";
break;
case AV_PIX_FMT_YUV444P16:
colorspace = " C444p16 XYSCSS=444P16";
break;
}
 
/* construct stream header, if this is the first frame */
n = snprintf(buf, Y4M_LINE_MAX, "%s W%d H%d F%d:%d I%c A%d:%d%s\n",
Y4M_MAGIC, width, height, raten, rated, inter,
aspectn, aspectd, colorspace);
 
return n;
}
 
static int yuv4_write_packet(AVFormatContext *s, AVPacket *pkt)
{
AVStream *st = s->streams[pkt->stream_index];
AVIOContext *pb = s->pb;
AVPicture *picture, picture_tmp;
int* first_pkt = s->priv_data;
int width, height, h_chroma_shift, v_chroma_shift;
int i;
char buf2[Y4M_LINE_MAX + 1];
char buf1[20];
uint8_t *ptr, *ptr1, *ptr2;
 
memcpy(&picture_tmp, pkt->data, sizeof(AVPicture));
picture = &picture_tmp;
 
/* for the first packet we have to output the header as well */
if (*first_pkt) {
*first_pkt = 0;
if (yuv4_generate_header(s, buf2) < 0) {
av_log(s, AV_LOG_ERROR,
"Error. YUV4MPEG stream header write failed.\n");
return AVERROR(EIO);
} else {
avio_write(pb, buf2, strlen(buf2));
}
}
 
/* construct frame header */
 
snprintf(buf1, sizeof(buf1), "%s\n", Y4M_FRAME_MAGIC);
avio_write(pb, buf1, strlen(buf1));
 
width = st->codec->width;
height = st->codec->height;
 
ptr = picture->data[0];
 
switch (st->codec->pix_fmt) {
case AV_PIX_FMT_GRAY8:
case AV_PIX_FMT_YUV411P:
case AV_PIX_FMT_YUV420P:
case AV_PIX_FMT_YUV422P:
case AV_PIX_FMT_YUV444P:
break;
case AV_PIX_FMT_GRAY16:
case AV_PIX_FMT_YUV420P9:
case AV_PIX_FMT_YUV422P9:
case AV_PIX_FMT_YUV444P9:
case AV_PIX_FMT_YUV420P10:
case AV_PIX_FMT_YUV422P10:
case AV_PIX_FMT_YUV444P10:
case AV_PIX_FMT_YUV420P12:
case AV_PIX_FMT_YUV422P12:
case AV_PIX_FMT_YUV444P12:
case AV_PIX_FMT_YUV420P14:
case AV_PIX_FMT_YUV422P14:
case AV_PIX_FMT_YUV444P14:
case AV_PIX_FMT_YUV420P16:
case AV_PIX_FMT_YUV422P16:
case AV_PIX_FMT_YUV444P16:
width *= 2;
break;
default:
av_log(s, AV_LOG_ERROR, "The pixel format '%s' is not supported.\n",
av_get_pix_fmt_name(st->codec->pix_fmt));
return AVERROR(EINVAL);
}
 
for (i = 0; i < height; i++) {
avio_write(pb, ptr, width);
ptr += picture->linesize[0];
}
 
if (st->codec->pix_fmt != AV_PIX_FMT_GRAY8 &&
st->codec->pix_fmt != AV_PIX_FMT_GRAY16) {
// Adjust for smaller Cb and Cr planes
av_pix_fmt_get_chroma_sub_sample(st->codec->pix_fmt, &h_chroma_shift,
&v_chroma_shift);
width = FF_CEIL_RSHIFT(width, h_chroma_shift);
height = FF_CEIL_RSHIFT(height, v_chroma_shift);
 
ptr1 = picture->data[1];
ptr2 = picture->data[2];
for (i = 0; i < height; i++) { /* Cb */
avio_write(pb, ptr1, width);
ptr1 += picture->linesize[1];
}
for (i = 0; i < height; i++) { /* Cr */
avio_write(pb, ptr2, width);
ptr2 += picture->linesize[2];
}
}
 
return 0;
}
 
static int yuv4_write_header(AVFormatContext *s)
{
int *first_pkt = s->priv_data;
 
if (s->nb_streams != 1)
return AVERROR(EIO);
 
if (s->streams[0]->codec->codec_id != AV_CODEC_ID_RAWVIDEO) {
av_log(s, AV_LOG_ERROR, "ERROR: Only rawvideo supported.\n");
return AVERROR_INVALIDDATA;
}
 
switch (s->streams[0]->codec->pix_fmt) {
case AV_PIX_FMT_YUV411P:
av_log(s, AV_LOG_WARNING, "Warning: generating rarely used 4:1:1 YUV "
"stream, some mjpegtools might not work.\n");
break;
case AV_PIX_FMT_GRAY8:
case AV_PIX_FMT_GRAY16:
case AV_PIX_FMT_YUV420P:
case AV_PIX_FMT_YUV422P:
case AV_PIX_FMT_YUV444P:
break;
case AV_PIX_FMT_YUV420P9:
case AV_PIX_FMT_YUV422P9:
case AV_PIX_FMT_YUV444P9:
case AV_PIX_FMT_YUV420P10:
case AV_PIX_FMT_YUV422P10:
case AV_PIX_FMT_YUV444P10:
case AV_PIX_FMT_YUV420P12:
case AV_PIX_FMT_YUV422P12:
case AV_PIX_FMT_YUV444P12:
case AV_PIX_FMT_YUV420P14:
case AV_PIX_FMT_YUV422P14:
case AV_PIX_FMT_YUV444P14:
case AV_PIX_FMT_YUV420P16:
case AV_PIX_FMT_YUV422P16:
case AV_PIX_FMT_YUV444P16:
if (s->streams[0]->codec->strict_std_compliance >= FF_COMPLIANCE_NORMAL) {
av_log(s, AV_LOG_ERROR, "'%s' is not a official yuv4mpegpipe pixel format. "
"Use '-strict -1' to encode to this pixel format.\n",
av_get_pix_fmt_name(s->streams[0]->codec->pix_fmt));
return AVERROR(EINVAL);
}
av_log(s, AV_LOG_WARNING, "Warning: generating non standard YUV stream. "
"Mjpegtools will not work.\n");
break;
default:
av_log(s, AV_LOG_ERROR, "ERROR: yuv4mpeg can only handle "
"yuv444p, yuv422p, yuv420p, yuv411p and gray8 pixel formats. "
"And using 'strict -1' also yuv444p9, yuv422p9, yuv420p9, "
"yuv444p10, yuv422p10, yuv420p10, "
"yuv444p12, yuv422p12, yuv420p12, "
"yuv444p14, yuv422p14, yuv420p14, "
"yuv444p16, yuv422p16, yuv420p16 "
"and gray16 pixel formats. "
"Use -pix_fmt to select one.\n");
return AVERROR(EIO);
}
 
*first_pkt = 1;
return 0;
}
 
AVOutputFormat ff_yuv4mpegpipe_muxer = {
.name = "yuv4mpegpipe",
.long_name = NULL_IF_CONFIG_SMALL("YUV4MPEG pipe"),
.extensions = "y4m",
.priv_data_size = sizeof(int),
.audio_codec = AV_CODEC_ID_NONE,
.video_codec = AV_CODEC_ID_RAWVIDEO,
.write_header = yuv4_write_header,
.write_packet = yuv4_write_packet,
.flags = AVFMT_RAWPICTURE,
};
#endif
 
/* 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, interlaced = '?';
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;
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("420p16", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P16;
} else if (strncmp("422p16", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV422P16;
} else if (strncmp("444p16", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV444P16;
} else if (strncmp("420p14", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P14;
} else if (strncmp("422p14", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV422P14;
} else if (strncmp("444p14", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV444P14;
} else if (strncmp("420p12", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P12;
} else if (strncmp("422p12", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV422P12;
} else if (strncmp("444p12", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV444P12;
} else if (strncmp("420p10", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P10;
} else if (strncmp("422p10", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV422P10;
} else if (strncmp("444p10", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_YUV444P10;
} else if (strncmp("420p9", tokstart, 5) == 0) {
pix_fmt = AV_PIX_FMT_YUV420P9;
} else if (strncmp("422p9", tokstart, 5) == 0) {
pix_fmt = AV_PIX_FMT_YUV422P9;
} else if (strncmp("444p9", tokstart, 5) == 0) {
pix_fmt = AV_PIX_FMT_YUV444P9;
} 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("mono16", tokstart, 6) == 0) {
pix_fmt = AV_PIX_FMT_GRAY16;
} 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
interlaced = *tokstart++;
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("420P9", tokstart, 5) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P9;
else if (strncmp("422P9", tokstart, 5) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV422P9;
else if (strncmp("444P9", tokstart, 5) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV444P9;
else if (strncmp("420P10", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P10;
else if (strncmp("422P10", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV422P10;
else if (strncmp("444P10", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV444P10;
else if (strncmp("420P12", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P12;
else if (strncmp("422P12", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV422P12;
else if (strncmp("444P12", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV444P12;
else if (strncmp("420P14", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P14;
else if (strncmp("422P14", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV422P14;
else if (strncmp("444P14", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV444P14;
else if (strncmp("420P16", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV420P16;
else if (strncmp("422P16", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV422P16;
else if (strncmp("444P16", tokstart, 6) == 0)
alt_pix_fmt = AV_PIX_FMT_YUV444P16;
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->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;
 
switch (interlaced){
case 'p':
st->codec->field_order = AV_FIELD_PROGRESSIVE;
break;
case 't':
st->codec->field_order = AV_FIELD_TB;
break;
case 'b':
st->codec->field_order = AV_FIELD_BT;
break;
case 'm':
av_log(s, AV_LOG_ERROR, "YUV4MPEG stream contains mixed "
"interlaced and non-interlaced frames.\n");
case '?':
st->codec->field_order = AV_FIELD_UNKNOWN;
break;
default:
av_log(s, AV_LOG_ERROR, "YUV4MPEG has invalid header.\n");
return AVERROR(EINVAL);
}
 
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;
}
 
#if CONFIG_YUV4MPEGPIPE_DEMUXER
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",
};
#endif