diff options
Diffstat (limited to 'libavdevice/v4l.c')
-rw-r--r-- | libavdevice/v4l.c | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/libavdevice/v4l.c b/libavdevice/v4l.c new file mode 100644 index 0000000000..e2f37d6d95 --- /dev/null +++ b/libavdevice/v4l.c @@ -0,0 +1,363 @@ +/* + * Linux video grab interface + * Copyright (c) 2000,2001 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 "avdevice.h" + +#undef __STRICT_ANSI__ //workaround due to broken kernel headers +#include "config.h" +#include "libavutil/rational.h" +#include "libavutil/imgutils.h" +#include "libavutil/log.h" +#include "libavutil/opt.h" +#include "libavformat/internal.h" +#include "libavcodec/dsputil.h" +#include <unistd.h> +#include <fcntl.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/time.h> +#define _LINUX_TIME_H 1 +#include <linux/videodev.h> +#include <time.h> +#include "avdevice.h" + +typedef struct { + AVClass *class; + int fd; + int frame_format; /* see VIDEO_PALETTE_xxx */ + int use_mmap; + AVRational time_base; + int64_t time_frame; + int frame_size; + struct video_capability video_cap; + struct video_audio audio_saved; + struct video_window video_win; + uint8_t *video_buf; + struct video_mbuf gb_buffers; + struct video_mmap gb_buf; + int gb_frame; + int standard; +} VideoData; + +static const struct { + int palette; + int depth; + enum AVPixelFormat pix_fmt; +} video_formats [] = { + {.palette = VIDEO_PALETTE_YUV420P, .depth = 12, .pix_fmt = AV_PIX_FMT_YUV420P }, + {.palette = VIDEO_PALETTE_YUV422, .depth = 16, .pix_fmt = AV_PIX_FMT_YUYV422 }, + {.palette = VIDEO_PALETTE_UYVY, .depth = 16, .pix_fmt = AV_PIX_FMT_UYVY422 }, + {.palette = VIDEO_PALETTE_YUYV, .depth = 16, .pix_fmt = AV_PIX_FMT_YUYV422 }, + /* NOTE: v4l uses BGR24, not RGB24 */ + {.palette = VIDEO_PALETTE_RGB24, .depth = 24, .pix_fmt = AV_PIX_FMT_BGR24 }, + {.palette = VIDEO_PALETTE_RGB565, .depth = 16, .pix_fmt = AV_PIX_FMT_BGR565 }, + {.palette = VIDEO_PALETTE_GREY, .depth = 8, .pix_fmt = AV_PIX_FMT_GRAY8 }, +}; + + +static int grab_read_header(AVFormatContext *s1, AVFormatParameters *ap) +{ + VideoData *s = s1->priv_data; + AVStream *st; + int video_fd; + int desired_palette, desired_depth; + struct video_tuner tuner; + struct video_audio audio; + struct video_picture pict; + int j; + int vformat_num = FF_ARRAY_ELEMS(video_formats); + + av_log(s1, AV_LOG_WARNING, "V4L input device is deprecated and will be removed in the next release."); + + if (ap->time_base.den <= 0) { + av_log(s1, AV_LOG_ERROR, "Wrong time base (%d)\n", ap->time_base.den); + return -1; + } + s->time_base = ap->time_base; + + s->video_win.width = ap->width; + s->video_win.height = ap->height; + + st = avformat_new_stream(s1, NULL); + if (!st) + return AVERROR(ENOMEM); + avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */ + + video_fd = open(s1->filename, O_RDWR); + if (video_fd < 0) { + av_log(s1, AV_LOG_ERROR, "%s: %s\n", s1->filename, strerror(errno)); + goto fail; + } + + if (ioctl(video_fd, VIDIOCGCAP, &s->video_cap) < 0) { + av_log(s1, AV_LOG_ERROR, "VIDIOCGCAP: %s\n", strerror(errno)); + goto fail; + } + + if (!(s->video_cap.type & VID_TYPE_CAPTURE)) { + av_log(s1, AV_LOG_ERROR, "Fatal: grab device does not handle capture\n"); + goto fail; + } + + /* no values set, autodetect them */ + if (s->video_win.width <= 0 || s->video_win.height <= 0) { + if (ioctl(video_fd, VIDIOCGWIN, &s->video_win, sizeof(s->video_win)) < 0) { + av_log(s1, AV_LOG_ERROR, "VIDIOCGWIN: %s\n", strerror(errno)); + goto fail; + } + } + + if(av_image_check_size(s->video_win.width, s->video_win.height, 0, s1) < 0) + return -1; + + desired_palette = -1; + desired_depth = -1; + for (j = 0; j < vformat_num; j++) { + if (ap->pix_fmt == video_formats[j].pix_fmt) { + desired_palette = video_formats[j].palette; + desired_depth = video_formats[j].depth; + break; + } + } + + /* set tv standard */ + if (!ioctl(video_fd, VIDIOCGTUNER, &tuner)) { + tuner.mode = s->standard; + ioctl(video_fd, VIDIOCSTUNER, &tuner); + } + + /* unmute audio */ + audio.audio = 0; + ioctl(video_fd, VIDIOCGAUDIO, &audio); + memcpy(&s->audio_saved, &audio, sizeof(audio)); + audio.flags &= ~VIDEO_AUDIO_MUTE; + ioctl(video_fd, VIDIOCSAUDIO, &audio); + + ioctl(video_fd, VIDIOCGPICT, &pict); + av_dlog(s1, "v4l: colour=%d hue=%d brightness=%d constrast=%d whiteness=%d\n", + pict.colour, pict.hue, pict.brightness, pict.contrast, pict.whiteness); + /* try to choose a suitable video format */ + pict.palette = desired_palette; + pict.depth= desired_depth; + if (desired_palette == -1 || ioctl(video_fd, VIDIOCSPICT, &pict) < 0) { + for (j = 0; j < vformat_num; j++) { + pict.palette = video_formats[j].palette; + pict.depth = video_formats[j].depth; + if (-1 != ioctl(video_fd, VIDIOCSPICT, &pict)) + break; + } + if (j >= vformat_num) + goto fail1; + } + + if (ioctl(video_fd, VIDIOCGMBUF, &s->gb_buffers) < 0) { + /* try to use read based access */ + int val; + + s->video_win.x = 0; + s->video_win.y = 0; + s->video_win.chromakey = -1; + s->video_win.flags = 0; + + if (ioctl(video_fd, VIDIOCSWIN, s->video_win) < 0) { + av_log(s1, AV_LOG_ERROR, "VIDIOCSWIN: %s\n", strerror(errno)); + goto fail; + } + + s->frame_format = pict.palette; + + val = 1; + if (ioctl(video_fd, VIDIOCCAPTURE, &val) < 0) { + av_log(s1, AV_LOG_ERROR, "VIDIOCCAPTURE: %s\n", strerror(errno)); + goto fail; + } + + s->time_frame = av_gettime() * s->time_base.den / s->time_base.num; + s->use_mmap = 0; + } else { + s->video_buf = mmap(0, s->gb_buffers.size, PROT_READ|PROT_WRITE, MAP_SHARED, video_fd, 0); + if ((unsigned char*)-1 == s->video_buf) { + s->video_buf = mmap(0, s->gb_buffers.size, PROT_READ|PROT_WRITE, MAP_PRIVATE, video_fd, 0); + if ((unsigned char*)-1 == s->video_buf) { + av_log(s1, AV_LOG_ERROR, "mmap: %s\n", strerror(errno)); + goto fail; + } + } + s->gb_frame = 0; + s->time_frame = av_gettime() * s->time_base.den / s->time_base.num; + + /* start to grab the first frame */ + s->gb_buf.frame = s->gb_frame % s->gb_buffers.frames; + s->gb_buf.height = s->video_win.height; + s->gb_buf.width = s->video_win.width; + s->gb_buf.format = pict.palette; + + if (ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf) < 0) { + if (errno != EAGAIN) { + fail1: + av_log(s1, AV_LOG_ERROR, "VIDIOCMCAPTURE: %s\n", strerror(errno)); + } else { + av_log(s1, AV_LOG_ERROR, "Fatal: grab device does not receive any video signal\n"); + } + goto fail; + } + for (j = 1; j < s->gb_buffers.frames; j++) { + s->gb_buf.frame = j; + ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf); + } + s->frame_format = s->gb_buf.format; + s->use_mmap = 1; + } + + for (j = 0; j < vformat_num; j++) { + if (s->frame_format == video_formats[j].palette) { + s->frame_size = s->video_win.width * s->video_win.height * video_formats[j].depth / 8; + st->codec->pix_fmt = video_formats[j].pix_fmt; + break; + } + } + + if (j >= vformat_num) + goto fail; + + s->fd = video_fd; + + st->codec->codec_type = AVMEDIA_TYPE_VIDEO; + st->codec->codec_id = AV_CODEC_ID_RAWVIDEO; + st->codec->width = s->video_win.width; + st->codec->height = s->video_win.height; + st->codec->time_base = s->time_base; + st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8; + + return 0; + fail: + if (video_fd >= 0) + close(video_fd); + return AVERROR(EIO); +} + +static int v4l_mm_read_picture(VideoData *s, uint8_t *buf) +{ + uint8_t *ptr; + + while (ioctl(s->fd, VIDIOCSYNC, &s->gb_frame) < 0 && + (errno == EAGAIN || errno == EINTR)); + + ptr = s->video_buf + s->gb_buffers.offsets[s->gb_frame]; + memcpy(buf, ptr, s->frame_size); + + /* Setup to capture the next frame */ + s->gb_buf.frame = s->gb_frame; + if (ioctl(s->fd, VIDIOCMCAPTURE, &s->gb_buf) < 0) { + if (errno == EAGAIN) + av_log(NULL, AV_LOG_ERROR, "Cannot Sync\n"); + else + av_log(NULL, AV_LOG_ERROR, "VIDIOCMCAPTURE: %s\n", strerror(errno)); + return AVERROR(EIO); + } + + /* This is now the grabbing frame */ + s->gb_frame = (s->gb_frame + 1) % s->gb_buffers.frames; + + return s->frame_size; +} + +static int grab_read_packet(AVFormatContext *s1, AVPacket *pkt) +{ + VideoData *s = s1->priv_data; + int64_t curtime, delay; + struct timespec ts; + + /* Calculate the time of the next frame */ + s->time_frame += INT64_C(1000000); + + /* wait based on the frame rate */ + for(;;) { + curtime = av_gettime(); + delay = s->time_frame * s->time_base.num / s->time_base.den - curtime; + if (delay <= 0) { + if (delay < INT64_C(-1000000) * s->time_base.num / s->time_base.den) { + /* printf("grabbing is %d frames late (dropping)\n", (int) -(delay / 16666)); */ + s->time_frame += INT64_C(1000000); + } + break; + } + ts.tv_sec = delay / 1000000; + ts.tv_nsec = (delay % 1000000) * 1000; + nanosleep(&ts, NULL); + } + + if (av_new_packet(pkt, s->frame_size) < 0) + return AVERROR(EIO); + + pkt->pts = curtime; + + /* read one frame */ + if (s->use_mmap) { + return v4l_mm_read_picture(s, pkt->data); + } else { + if (read(s->fd, pkt->data, pkt->size) != pkt->size) + return AVERROR(EIO); + return s->frame_size; + } +} + +static int grab_read_close(AVFormatContext *s1) +{ + VideoData *s = s1->priv_data; + + if (s->use_mmap) + munmap(s->video_buf, s->gb_buffers.size); + + /* mute audio. we must force it because the BTTV driver does not + return its state correctly */ + s->audio_saved.flags |= VIDEO_AUDIO_MUTE; + ioctl(s->fd, VIDIOCSAUDIO, &s->audio_saved); + + close(s->fd); + return 0; +} + +static const AVOption options[] = { + { "standard", "", offsetof(VideoData, standard), AV_OPT_TYPE_INT, {.i64 = VIDEO_MODE_NTSC}, VIDEO_MODE_PAL, VIDEO_MODE_NTSC, AV_OPT_FLAG_DECODING_PARAM, "standard" }, + { "PAL", "", 0, AV_OPT_TYPE_CONST, {.i64 = VIDEO_MODE_PAL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, + { "SECAM", "", 0, AV_OPT_TYPE_CONST, {.i64 = VIDEO_MODE_SECAM}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, + { "NTSC", "", 0, AV_OPT_TYPE_CONST, {.i64 = VIDEO_MODE_NTSC}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, + { NULL }, +}; + +static const AVClass v4l_class = { + .class_name = "V4L indev", + .item_name = av_default_item_name, + .option = options, + .version = LIBAVUTIL_VERSION_INT, +}; + +AVInputFormat ff_v4l_demuxer = { + .name = "video4linux,v4l", + .long_name = NULL_IF_CONFIG_SMALL("Video4Linux device grab"), + .priv_data_size = sizeof(VideoData), + .read_header = grab_read_header, + .read_packet = grab_read_packet, + .read_close = grab_read_close, + .flags = AVFMT_NOFILE, + .priv_class = &v4l_class, +}; |