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/*
* Linux DV1394 interface
* Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com>
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "config.h"
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <poll.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <time.h>
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "libavformat/avformat.h"
#include "libavformat/dv.h"
#include "dv1394.h"
struct dv1394_data {
AVClass *class;
int fd;
int channel;
int format;
uint8_t *ring; /* Ring buffer */
int index; /* Current frame index */
int avail; /* Number of frames available for reading */
int done; /* Number of completed frames */
DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */
};
/*
* The trick here is to kludge around well known problem with kernel Ooopsing
* when you try to capture PAL on a device node configure for NTSC. That's
* why we have to configure the device node for PAL, and then read only NTSC
* amount of data.
*/
static int dv1394_reset(struct dv1394_data *dv)
{
struct dv1394_init init;
init.channel = dv->channel;
init.api_version = DV1394_API_VERSION;
init.n_frames = DV1394_RING_FRAMES;
init.format = DV1394_PAL;
if (ioctl(dv->fd, DV1394_INIT, &init) < 0)
return -1;
dv->avail = dv->done = 0;
return 0;
}
static int dv1394_start(struct dv1394_data *dv)
{
/* Tell DV1394 driver to enable receiver */
if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) {
av_log(NULL, AV_LOG_ERROR, "Failed to start receiver: %s\n", strerror(errno));
return -1;
}
return 0;
}
static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap)
{
struct dv1394_data *dv = context->priv_data;
dv->dv_demux = avpriv_dv_init_demux(context);
if (!dv->dv_demux)
goto failed;
/* Open and initialize DV1394 device */
dv->fd = open(context->filename, O_RDONLY);
if (dv->fd < 0) {
av_log(context, AV_LOG_ERROR, "Failed to open DV interface: %s\n", strerror(errno));
goto failed;
}
if (dv1394_reset(dv) < 0) {
av_log(context, AV_LOG_ERROR, "Failed to initialize DV interface: %s\n", strerror(errno));
goto failed;
}
dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES,
PROT_READ, MAP_PRIVATE, dv->fd, 0);
if (dv->ring == MAP_FAILED) {
av_log(context, AV_LOG_ERROR, "Failed to mmap DV ring buffer: %s\n", strerror(errno));
goto failed;
}
if (dv1394_start(dv) < 0)
goto failed;
return 0;
failed:
close(dv->fd);
return AVERROR(EIO);
}
static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt)
{
struct dv1394_data *dv = context->priv_data;
int size;
size = avpriv_dv_get_packet(dv->dv_demux, pkt);
if (size > 0)
return size;
if (!dv->avail) {
struct dv1394_status s;
struct pollfd p;
if (dv->done) {
/* Request more frames */
if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) {
/* This usually means that ring buffer overflowed.
* We have to reset :(.
*/
av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n");
dv1394_reset(dv);
dv1394_start(dv);
}
dv->done = 0;
}
/* Wait until more frames are available */
restart_poll:
p.fd = dv->fd;
p.events = POLLIN | POLLERR | POLLHUP;
if (poll(&p, 1, -1) < 0) {
if (errno == EAGAIN || errno == EINTR)
goto restart_poll;
av_log(context, AV_LOG_ERROR, "Poll failed: %s\n", strerror(errno));
return AVERROR(EIO);
}
if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) {
av_log(context, AV_LOG_ERROR, "Failed to get status: %s\n", strerror(errno));
return AVERROR(EIO);
}
av_dlog(context, "DV1394: status\n"
"\tactive_frame\t%d\n"
"\tfirst_clear_frame\t%d\n"
"\tn_clear_frames\t%d\n"
"\tdropped_frames\t%d\n",
s.active_frame, s.first_clear_frame,
s.n_clear_frames, s.dropped_frames);
dv->avail = s.n_clear_frames;
dv->index = s.first_clear_frame;
dv->done = 0;
if (s.dropped_frames) {
av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n",
s.dropped_frames);
dv1394_reset(dv);
dv1394_start(dv);
}
}
av_dlog(context, "index %d, avail %d, done %d\n", dv->index, dv->avail,
dv->done);
size = avpriv_dv_produce_packet(dv->dv_demux, pkt,
dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE),
DV1394_PAL_FRAME_SIZE);
dv->index = (dv->index + 1) % DV1394_RING_FRAMES;
dv->done++; dv->avail--;
return size;
}
static int dv1394_close(AVFormatContext * context)
{
struct dv1394_data *dv = context->priv_data;
/* Shutdown DV1394 receiver */
if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0)
av_log(context, AV_LOG_ERROR, "Failed to shutdown DV1394: %s\n", strerror(errno));
/* Unmap ring buffer */
if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0)
av_log(context, AV_LOG_ERROR, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno));
close(dv->fd);
av_free(dv->dv_demux);
return 0;
}
static const AVOption options[] = {
{ "standard", "", offsetof(struct dv1394_data, format), AV_OPT_TYPE_INT, {.dbl = DV1394_NTSC}, DV1394_PAL, DV1394_NTSC, AV_OPT_FLAG_DECODING_PARAM, "standard" },
{ "PAL", "", 0, AV_OPT_TYPE_CONST, {.dbl = DV1394_PAL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" },
{ "NTSC", "", 0, AV_OPT_TYPE_CONST, {.dbl = DV1394_NTSC}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" },
{ "channel", "", offsetof(struct dv1394_data, channel), AV_OPT_TYPE_INT, {.dbl = DV1394_DEFAULT_CHANNEL}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
{ NULL },
};
static const AVClass dv1394_class = {
.class_name = "DV1394 indev",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
AVInputFormat ff_dv1394_demuxer = {
.name = "dv1394",
.long_name = NULL_IF_CONFIG_SMALL("DV1394 A/V grab"),
.priv_data_size = sizeof(struct dv1394_data),
.read_header = dv1394_read_header,
.read_packet = dv1394_read_packet,
.read_close = dv1394_close,
.flags = AVFMT_NOFILE,
.priv_class = &dv1394_class,
};
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