| 1 | /* |
| 2 | * Copyright (c) 2013 Clément Bœsch |
| 3 | * |
| 4 | * This file is part of FFmpeg. |
| 5 | * |
| 6 | * FFmpeg is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * FFmpeg is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with FFmpeg; if not, write to the Free Software |
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 19 | */ |
| 20 | |
| 21 | #include "v4l2-common.h" |
| 22 | #include "avdevice.h" |
| 23 | |
| 24 | typedef struct { |
| 25 | AVClass *class; |
| 26 | int fd; |
| 27 | } V4L2Context; |
| 28 | |
| 29 | static av_cold int write_header(AVFormatContext *s1) |
| 30 | { |
| 31 | int res = 0, flags = O_RDWR; |
| 32 | struct v4l2_format fmt = { |
| 33 | .type = V4L2_BUF_TYPE_VIDEO_OUTPUT |
| 34 | }; |
| 35 | V4L2Context *s = s1->priv_data; |
| 36 | AVCodecContext *enc_ctx; |
| 37 | uint32_t v4l2_pixfmt; |
| 38 | |
| 39 | if (s1->flags & AVFMT_FLAG_NONBLOCK) |
| 40 | flags |= O_NONBLOCK; |
| 41 | |
| 42 | s->fd = open(s1->filename, flags); |
| 43 | if (s->fd < 0) { |
| 44 | res = AVERROR(errno); |
| 45 | av_log(s1, AV_LOG_ERROR, "Unable to open V4L2 device '%s'\n", s1->filename); |
| 46 | return res; |
| 47 | } |
| 48 | |
| 49 | if (s1->nb_streams != 1 || |
| 50 | s1->streams[0]->codec->codec_type != AVMEDIA_TYPE_VIDEO || |
| 51 | s1->streams[0]->codec->codec_id != AV_CODEC_ID_RAWVIDEO) { |
| 52 | av_log(s1, AV_LOG_ERROR, |
| 53 | "V4L2 output device supports only a single raw video stream\n"); |
| 54 | return AVERROR(EINVAL); |
| 55 | } |
| 56 | |
| 57 | enc_ctx = s1->streams[0]->codec; |
| 58 | |
| 59 | v4l2_pixfmt = ff_fmt_ff2v4l(enc_ctx->pix_fmt, AV_CODEC_ID_RAWVIDEO); |
| 60 | if (!v4l2_pixfmt) { // XXX: try to force them one by one? |
| 61 | av_log(s1, AV_LOG_ERROR, "Unknown V4L2 pixel format equivalent for %s\n", |
| 62 | av_get_pix_fmt_name(enc_ctx->pix_fmt)); |
| 63 | return AVERROR(EINVAL); |
| 64 | } |
| 65 | |
| 66 | if (ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) { |
| 67 | res = AVERROR(errno); |
| 68 | av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", av_err2str(res)); |
| 69 | return res; |
| 70 | } |
| 71 | |
| 72 | fmt.fmt.pix.width = enc_ctx->width; |
| 73 | fmt.fmt.pix.height = enc_ctx->height; |
| 74 | fmt.fmt.pix.pixelformat = v4l2_pixfmt; |
| 75 | fmt.fmt.pix.sizeimage = av_image_get_buffer_size(enc_ctx->pix_fmt, enc_ctx->width, enc_ctx->height, 1); |
| 76 | |
| 77 | if (ioctl(s->fd, VIDIOC_S_FMT, &fmt) < 0) { |
| 78 | res = AVERROR(errno); |
| 79 | av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_FMT): %s\n", av_err2str(res)); |
| 80 | return res; |
| 81 | } |
| 82 | |
| 83 | return res; |
| 84 | } |
| 85 | |
| 86 | static int write_packet(AVFormatContext *s1, AVPacket *pkt) |
| 87 | { |
| 88 | const V4L2Context *s = s1->priv_data; |
| 89 | if (write(s->fd, pkt->data, pkt->size) == -1) |
| 90 | return AVERROR(errno); |
| 91 | return 0; |
| 92 | } |
| 93 | |
| 94 | static int write_trailer(AVFormatContext *s1) |
| 95 | { |
| 96 | const V4L2Context *s = s1->priv_data; |
| 97 | close(s->fd); |
| 98 | return 0; |
| 99 | } |
| 100 | |
| 101 | static const AVClass v4l2_class = { |
| 102 | .class_name = "V4L2 outdev", |
| 103 | .item_name = av_default_item_name, |
| 104 | .version = LIBAVUTIL_VERSION_INT, |
| 105 | .category = AV_CLASS_CATEGORY_DEVICE_VIDEO_OUTPUT, |
| 106 | }; |
| 107 | |
| 108 | AVOutputFormat ff_v4l2_muxer = { |
| 109 | .name = "v4l2", |
| 110 | .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 output device"), |
| 111 | .priv_data_size = sizeof(V4L2Context), |
| 112 | .audio_codec = AV_CODEC_ID_NONE, |
| 113 | .video_codec = AV_CODEC_ID_RAWVIDEO, |
| 114 | .write_header = write_header, |
| 115 | .write_packet = write_packet, |
| 116 | .write_trailer = write_trailer, |
| 117 | .flags = AVFMT_NOFILE, |
| 118 | .priv_class = &v4l2_class, |
| 119 | }; |