3 * Copyright (c) 2001, 2002, 2003 Fabrice Bellard
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 #include "libavutil/pixdesc.h"
27 #define Y4M_LINE_MAX 256
29 static int yuv4_generate_header(AVFormatContext *s, char* buf)
33 int raten, rated, aspectn, aspectd, n;
35 const char *colorspace = "";
38 width = st->codec->width;
39 height = st->codec->height;
41 // TODO: should be avg_frame_rate
42 av_reduce(&raten, &rated, st->time_base.den,
43 st->time_base.num, (1UL << 31) - 1);
45 aspectn = st->sample_aspect_ratio.num;
46 aspectd = st->sample_aspect_ratio.den;
48 if (aspectn == 0 && aspectd == 1)
49 aspectd = 0; // 0:0 means unknown
51 switch (st->codec->field_order) {
52 case AV_FIELD_TT: inter = 't'; break;
53 case AV_FIELD_BB: inter = 'b'; break;
54 default: inter = 'p'; break;
57 switch (st->codec->pix_fmt) {
58 case AV_PIX_FMT_GRAY8:
59 colorspace = " Cmono";
61 case AV_PIX_FMT_YUV411P:
62 colorspace = " C411 XYSCSS=411";
64 case AV_PIX_FMT_YUV420P:
65 switch (st->codec->chroma_sample_location) {
66 case AVCHROMA_LOC_TOPLEFT: colorspace = " C420paldv XYSCSS=420PALDV"; break;
67 case AVCHROMA_LOC_LEFT: colorspace = " C420mpeg2 XYSCSS=420MPEG2"; break;
68 default: colorspace = " C420jpeg XYSCSS=420JPEG"; break;
71 case AV_PIX_FMT_YUV422P:
72 colorspace = " C422 XYSCSS=422";
74 case AV_PIX_FMT_YUV444P:
75 colorspace = " C444 XYSCSS=444";
79 /* construct stream header, if this is the first frame */
80 n = snprintf(buf, Y4M_LINE_MAX, "%s W%d H%d F%d:%d I%c A%d:%d%s\n",
81 Y4M_MAGIC, width, height, raten, rated, inter,
82 aspectn, aspectd, colorspace);
87 static int yuv4_write_packet(AVFormatContext *s, AVPacket *pkt)
89 AVStream *st = s->streams[pkt->stream_index];
90 AVIOContext *pb = s->pb;
92 int* first_pkt = s->priv_data;
93 int width, height, h_chroma_shift, v_chroma_shift;
95 char buf2[Y4M_LINE_MAX + 1];
97 uint8_t *ptr, *ptr1, *ptr2;
99 picture = (AVPicture *)pkt->data;
101 /* for the first packet we have to output the header as well */
104 if (yuv4_generate_header(s, buf2) < 0) {
105 av_log(s, AV_LOG_ERROR,
106 "Error. YUV4MPEG stream header write failed.\n");
109 avio_write(pb, buf2, strlen(buf2));
113 /* construct frame header */
115 snprintf(buf1, sizeof(buf1), "%s\n", Y4M_FRAME_MAGIC);
116 avio_write(pb, buf1, strlen(buf1));
118 width = st->codec->width;
119 height = st->codec->height;
121 ptr = picture->data[0];
122 for (i = 0; i < height; i++) {
123 avio_write(pb, ptr, width);
124 ptr += picture->linesize[0];
127 if (st->codec->pix_fmt != AV_PIX_FMT_GRAY8) {
128 // Adjust for smaller Cb and Cr planes
129 av_pix_fmt_get_chroma_sub_sample(st->codec->pix_fmt, &h_chroma_shift,
131 // Shift right, rounding up
132 width = -(-width >> h_chroma_shift);
133 height = -(-height >> v_chroma_shift);
135 ptr1 = picture->data[1];
136 ptr2 = picture->data[2];
137 for (i = 0; i < height; i++) { /* Cb */
138 avio_write(pb, ptr1, width);
139 ptr1 += picture->linesize[1];
141 for (i = 0; i < height; i++) { /* Cr */
142 avio_write(pb, ptr2, width);
143 ptr2 += picture->linesize[2];
149 static int yuv4_write_header(AVFormatContext *s)
151 int *first_pkt = s->priv_data;
153 if (s->nb_streams != 1)
156 if (s->streams[0]->codec->codec_id != AV_CODEC_ID_RAWVIDEO) {
157 av_log(s, AV_LOG_ERROR, "ERROR: Only rawvideo supported.\n");
158 return AVERROR_INVALIDDATA;
161 if (s->streams[0]->codec->pix_fmt == AV_PIX_FMT_YUV411P) {
162 av_log(s, AV_LOG_ERROR, "Warning: generating rarely used 4:1:1 YUV "
163 "stream, some mjpegtools might not work.\n");
164 } else if ((s->streams[0]->codec->pix_fmt != AV_PIX_FMT_YUV420P) &&
165 (s->streams[0]->codec->pix_fmt != AV_PIX_FMT_YUV422P) &&
166 (s->streams[0]->codec->pix_fmt != AV_PIX_FMT_GRAY8) &&
167 (s->streams[0]->codec->pix_fmt != AV_PIX_FMT_YUV444P)) {
168 av_log(s, AV_LOG_ERROR, "ERROR: yuv4mpeg only handles yuv444p, "
169 "yuv422p, yuv420p, yuv411p and gray pixel formats. "
170 "Use -pix_fmt to select one.\n");
178 AVOutputFormat ff_yuv4mpegpipe_muxer = {
179 .name = "yuv4mpegpipe",
180 .long_name = NULL_IF_CONFIG_SMALL("YUV4MPEG pipe"),
183 .priv_data_size = sizeof(int),
184 .audio_codec = AV_CODEC_ID_NONE,
185 .video_codec = AV_CODEC_ID_RAWVIDEO,
186 .write_header = yuv4_write_header,
187 .write_packet = yuv4_write_packet,
188 .flags = AVFMT_RAWPICTURE,