diff options
Diffstat (limited to 'libavdevice/dv1394.c')
| -rw-r--r-- | libavdevice/dv1394.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/libavdevice/dv1394.c b/libavdevice/dv1394.c new file mode 100644 index 0000000000..8e2e2f607c --- /dev/null +++ b/libavdevice/dv1394.c @@ -0,0 +1,236 @@ +/* + * Linux DV1394 interface + * Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com> + * + * 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 <unistd.h> +#include <fcntl.h> +#include <errno.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/poll.h> +#include <sys/time.h> +#include <time.h> + +#include "avformat.h" + +#undef DV1394_DEBUG + +#include "dv1394.h" +#include "dv.h" + +struct dv1394_data { + 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 = dv_init_demux(context); + if (!dv->dv_demux) + goto failed; + + if (ap->standard && !strcasecmp(ap->standard, "pal")) + dv->format = DV1394_PAL; + else + dv->format = DV1394_NTSC; + + if (ap->channel) + dv->channel = ap->channel; + else + dv->channel = DV1394_DEFAULT_CHANNEL; + + /* 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 = 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); + } +#ifdef DV1394_DEBUG + av_log(context, AV_LOG_DEBUG, "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); +#endif + + 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); + } + } + +#ifdef DV1394_DEBUG + av_log(context, AV_LOG_DEBUG, "index %d, avail %d, done %d\n", dv->index, dv->avail, + dv->done); +#endif + + size = 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; +} + +AVInputFormat dv1394_demuxer = { + .name = "dv1394", + .long_name = "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 +}; |