grab.c

FFmpeg is an audio/video conversion tool. It includes libavcodec, the leading open source codec libr

/*
 * Linux video grab interface
 * Copyright (c) 2000,2001 Fabrice Bellard.
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include "avformat.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>

typedef struct {
    int fd;
    int frame_format; /* see VIDEO_PALETTE_xxx */
    int use_mmap;
    int width, height;
    int frame_rate;
    int frame_rate_base;
    int64_t time_frame;
    int frame_size;
    struct video_capability video_cap;
    struct video_audio audio_saved;
    uint8_t *video_buf;
    struct video_mbuf gb_buffers;
    struct video_mmap gb_buf;
    int gb_frame;

    /* ATI All In Wonder specific stuff */
    /* XXX: remove and merge in libavcodec/imgconvert.c */
    int aiw_enabled;
    int deint;
    int halfw;
    uint8_t *src_mem;
    uint8_t *lum_m4_mem;
} VideoData;

static int aiw_init(VideoData *s);
static int aiw_read_picture(VideoData *s, uint8_t *data);
static int aiw_close(VideoData *s);

static int grab_read_header(AVFormatContext *s1, AVFormatParameters *ap)
{
    VideoData *s = s1->priv_data;
    AVStream *st;
    int width, height;
    int video_fd, frame_size;
    int ret, frame_rate, frame_rate_base;
    int desired_palette;
    struct video_tuner tuner;
    struct video_audio audio;
    const char *video_device;
    int j;

    if (!ap || ap->width <= 0 || ap->height <= 0 || ap->frame_rate <= 0)
        return -1;
    
    width = ap->width;
    height = ap->height;
    frame_rate      = ap->frame_rate;
    frame_rate_base = ap->frame_rate_base;

    st = av_new_stream(s1, 0);
    if (!st)
        return -ENOMEM;
    av_set_pts_info(st, 48, 1, 1000000); /* 48 bits pts in us */

    s->width = width;
    s->height = height;
    s->frame_rate      = frame_rate;
    s->frame_rate_base = frame_rate_base;

    video_device = ap->device;
    if (!video_device)
        video_device = "/dev/video";
    video_fd = open(video_device, O_RDWR);
    if (video_fd < 0) {
        perror(video_device);
        goto fail;
    }
    
    if (ioctl(video_fd,VIDIOCGCAP, &s->video_cap) < 0) {
        perror("VIDIOCGCAP");
        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;
    }

    desired_palette = -1;
    if (st->codec.pix_fmt == PIX_FMT_YUV420P) {
        desired_palette = VIDEO_PALETTE_YUV420P;
    } else if (st->codec.pix_fmt == PIX_FMT_YUV422) {
        desired_palette = VIDEO_PALETTE_YUV422;
    } else if (st->codec.pix_fmt == PIX_FMT_BGR24) {
        desired_palette = VIDEO_PALETTE_RGB24;
    }    

    /* set tv standard */
    if (ap->standard && !ioctl(video_fd, VIDIOCGTUNER, &tuner)) {
	if (!strcasecmp(ap->standard, "pal"))
	    tuner.mode = VIDEO_MODE_PAL;
	else if (!strcasecmp(ap->standard, "secam"))
	    tuner.mode = VIDEO_MODE_SECAM;
	else
	    tuner.mode = VIDEO_MODE_NTSC;
	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);

    ret = ioctl(video_fd,VIDIOCGMBUF,&s->gb_buffers);
    if (ret < 0) {
        /* try to use read based access */
        struct video_window win;
        struct video_picture pict;
        int val;

        win.x = 0;
        win.y = 0;
        win.width = width;
        win.height = height;
        win.chromakey = -1;
        win.flags = 0;

        ioctl(video_fd, VIDIOCSWIN, &win);

        ioctl(video_fd, VIDIOCGPICT, &pict);
#if 0
        printf("v4l: colour=%d hue=%d brightness=%d constrast=%d whiteness=%d\n",
               pict.colour,
               pict.hue,
               pict.brightness,
               pict.contrast,
               pict.whiteness);
#endif        
        /* try to choose a suitable video format */
        pict.palette = desired_palette;
        if (desired_palette == -1 || (ret = ioctl(video_fd, VIDIOCSPICT, &pict)) < 0) {
            pict.palette=VIDEO_PALETTE_YUV420P;
            ret = ioctl(video_fd, VIDIOCSPICT, &pict);
            if (ret < 0) {
                pict.palette=VIDEO_PALETTE_YUV422;
                ret = ioctl(video_fd, VIDIOCSPICT, &pict);
                if (ret < 0) {
                    pict.palette=VIDEO_PALETTE_RGB24;
                    ret = ioctl(video_fd, VIDIOCSPICT, &pict);
                    if (ret < 0) 
                        goto fail1;
                }
            }
        }

        s->frame_format = pict.palette;

        val = 1;
        ioctl(video_fd, VIDIOCCAPTURE, &val);

        s->time_frame = av_gettime() * s->frame_rate / s->frame_rate_base;
        s->use_mmap = 0;
        
        /* ATI All In Wonder automatic activation */
        if (!strcmp(s->video_cap.name, "Km")) {
            if (aiw_init(s) < 0)
                goto fail;
            s->aiw_enabled = 1;
            /* force 420P format because convertion from YUV422 to YUV420P
               is done in this driver (ugly) */
            s->frame_format = VIDEO_PALETTE_YUV420P;
        }
    } 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) {
            perror("mmap");
            goto fail;
        }
        s->gb_frame = 0;
        s->time_frame = av_gettime() * s->frame_rate / s->frame_rate_base;
        
        /* start to grab the first frame */
        s->gb_buf.frame = s->gb_frame % s->gb_buffers.frames;
        s->gb_buf.height = height;
        s->gb_buf.width = width;
        s->gb_buf.format = desired_palette;

        if (desired_palette == -1 || (ret = ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf)) < 0) {
            s->gb_buf.format = VIDEO_PALETTE_YUV420P;
            
            ret = ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf);
            if (ret < 0 && errno != EAGAIN) {
                /* try YUV422 */
                s->gb_buf.format = VIDEO_PALETTE_YUV422;
                
                ret = ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf);
                if (ret < 0 && errno != EAGAIN) {
                    /* try RGB24 */
                    s->gb_buf.format = VIDEO_PALETTE_RGB24;
                    ret = ioctl(video_fd, VIDIOCMCAPTURE, &s->gb_buf);
                }
            }
        }
        if (ret < 0) {
            if (errno != EAGAIN) {
            fail1:
                av_log(s1, AV_LOG_ERROR, "Fatal: grab device does not support suitable format\n");
            } 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;
    }

    switch(s->frame_format) {
    case VIDEO_PALETTE_YUV420P:
        frame_size = (width * height * 3) / 2;
        st->codec.pix_fmt = PIX_FMT_YUV420P;
        break;
    case VIDEO_PALETTE_YUV422:
        frame_size = width * height * 2;
        st->codec.pix_fmt = PIX_FMT_YUV422;
        break;
    case VIDEO_PALETTE_RGB24:
        frame_size = width * height * 3;
        st->codec.pix_fmt = PIX_FMT_BGR24; /* NOTE: v4l uses BGR24, not RGB24 ! */
        break;
    default:
        goto fail;
    }
    s->fd = video_fd;
    s->frame_size = frame_size;
    
    st->codec.codec_type = CODEC_TYPE_VIDEO;
    st->codec.codec_id = CODEC_ID_RAWVIDEO;
    st->codec.width = width;
    st->codec.height = height;
    st->codec.frame_rate      = frame_rate;
    st->codec.frame_rate_base = frame_rate_base;

    return 0;
 fail:
    if (video_fd >= 0)
        close(video_fd);
    av_free(st);
    return AVERROR_IO;
}

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
            perror("VIDIOCMCAPTURE");
        return AVERROR_IO;
    }

    /* 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_t_C(1000000);

    /* wait based on the frame rate */
    for(;;) {
        curtime = av_gettime();
        delay = s->time_frame  * s->frame_rate_base / s->frame_rate - curtime;
        if (delay <= 0) {
            if (delay < int64_t_C(-1000000) * s->frame_rate_base / s->frame_rate) {
                /* printf("grabbing is %d frames late (dropping)\n", (int) -(delay / 16666)); */
                s->time_frame += int64_t_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_IO;

    pkt->pts = curtime & ((1LL << 48) - 1);

    /* read one frame */
    if (s->aiw_enabled) {
        return aiw_read_picture(s, pkt->data);
    } else 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_IO;
        return s->frame_size;
    }
}

static int grab_read_close(AVFormatContext *s1)
{
    VideoData *s = s1->priv_data;

    if (s->aiw_enabled)
        aiw_close(s);

    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 AVInputFormat video_grab_device_format = {
    "video4linux",
    "video grab",
    sizeof(VideoData),
    NULL,
    grab_read_header,
    grab_read_packet,
    grab_read_close,
    .flags = AVFMT_NOFILE,
};

/* All in Wonder specific stuff */
/* XXX: remove and merge in libavcodec/imgconvert.c */

static int aiw_init(VideoData *s)
{
    int width, height;

    width = s->width;
    height = s->height;

    if ((width == s->video_cap.maxwidth && height == s->video_cap.maxheight) ||
        (width == s->video_cap.maxwidth && height == s->video_cap.maxheight*2) ||
        (width == s->video_cap.maxwidth/2 && height == s->video_cap.maxheight)) {
        
        s->deint=0;
        s->halfw=0;
        if (height == s->video_cap.maxheight*2) s->deint=1;
        if (width == s->video_cap.maxwidth/2) s->halfw=1;
    } else {
        av_log(NULL, AV_LOG_ERROR, "\nIncorrect Grab Size Supplied - Supported Sizes Are:\n");
        av_log(NULL, AV_LOG_ERROR, " %dx%d  %dx%d %dx%d\n\n",
                s->video_cap.maxwidth,s->video_cap.maxheight,
                s->video_cap.maxwidth,s->video_cap.maxheight*2,
                s->video_cap.maxwidth/2,s->video_cap.maxheight);
        goto fail;
    }

    if (s->halfw == 0) {
        s->src_mem = av_malloc(s->width*2);
    } else {
        s->src_mem = av_malloc(s->width*4);
    }
    if (!s->src_mem) goto fail;

    s->lum_m4_mem = av_malloc(s->width);
    if (!s->lum_m4_mem)
        goto fail;
    return 0;
 fail:
    av_freep(&s->src_mem);
    av_freep(&s->lum_m4_mem);
    return -1;
}

#ifdef HAVE_MMX
#include "../libavcodec/i386/mmx.h"

#define LINE_WITH_UV \
                    movq_m2r(ptr[0],mm0); \
                    movq_m2r(ptr[8],mm1);  \
                    movq_r2r(mm0, mm4); \
                    punpcklbw_r2r(mm1,mm0); \
                    punpckhbw_r2r(mm1,mm4); \