/* * 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 "libavutil/internal.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) { 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 = avpriv_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, {.i64 = DV1394_NTSC}, DV1394_NTSC, DV1394_PAL, AV_OPT_FLAG_DECODING_PARAM, "standard" }, { "PAL", "", 0, AV_OPT_TYPE_CONST, {.i64 = DV1394_PAL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, { "NTSC", "", 0, AV_OPT_TYPE_CONST, {.i64 = DV1394_NTSC}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, { "channel", "", offsetof(struct dv1394_data, channel), AV_OPT_TYPE_INT, {.i64 = 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, };