mirror of https://github.com/FFmpeg/FFmpeg.git
Support for this device has been removed in the Linux kernel since v2.6.37. dv1394 has been superseded by libiec61883 which is functionally equivalent. Signed-off-by: Josh de Kock <josh@itanimul.li> Signed-off-by: Diego Biurrun <diego@biurrun.de>pull/272/head
Josh de Kock
7 years ago
committed by
Diego Biurrun
parent
543f00c78e
commit
762ab2de6e
8 changed files with 1 additions and 606 deletions
@ -1,238 +0,0 @@ |
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/*
|
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* Linux DV1394 interface |
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* Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com> |
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* |
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* This file is part of Libav. |
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* |
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* Libav is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* Libav is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with Libav; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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|
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#include "config.h" |
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#include <unistd.h> |
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#include <fcntl.h> |
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#include <errno.h> |
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#include <poll.h> |
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#include <sys/ioctl.h> |
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#include <sys/mman.h> |
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|
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#include "libavutil/internal.h" |
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#include "libavutil/log.h" |
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#include "libavutil/opt.h" |
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#include "libavformat/avformat.h" |
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#include "libavformat/dv.h" |
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#include "dv1394.h" |
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|
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struct dv1394_data { |
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AVClass *class; |
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int fd; |
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int channel; |
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int format; |
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uint8_t *ring; /* Ring buffer */ |
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int index; /* Current frame index */ |
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int avail; /* Number of frames available for reading */ |
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int done; /* Number of completed frames */ |
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DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */ |
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}; |
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/*
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* The trick here is to kludge around well known problem with kernel Ooopsing |
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* when you try to capture PAL on a device node configure for NTSC. That's |
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* why we have to configure the device node for PAL, and then read only NTSC |
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* amount of data. |
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*/ |
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static int dv1394_reset(struct dv1394_data *dv) |
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{ |
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struct dv1394_init init; |
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init.channel = dv->channel; |
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init.api_version = DV1394_API_VERSION; |
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init.n_frames = DV1394_RING_FRAMES; |
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init.format = DV1394_PAL; |
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if (ioctl(dv->fd, DV1394_INIT, &init) < 0) |
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return -1; |
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dv->avail = dv->done = 0; |
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return 0; |
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} |
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static int dv1394_start(struct dv1394_data *dv) |
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{ |
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/* Tell DV1394 driver to enable receiver */ |
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if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) { |
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av_log(NULL, AV_LOG_ERROR, "Failed to start receiver: %s\n", strerror(errno)); |
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return -1; |
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} |
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return 0; |
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} |
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static int dv1394_read_header(AVFormatContext * context) |
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{ |
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struct dv1394_data *dv = context->priv_data; |
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dv->dv_demux = avpriv_dv_init_demux(context); |
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if (!dv->dv_demux) |
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goto failed; |
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/* Open and initialize DV1394 device */ |
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dv->fd = avpriv_open(context->filename, O_RDONLY); |
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if (dv->fd < 0) { |
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av_log(context, AV_LOG_ERROR, "Failed to open DV interface: %s\n", strerror(errno)); |
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goto failed; |
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} |
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if (dv1394_reset(dv) < 0) { |
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av_log(context, AV_LOG_ERROR, "Failed to initialize DV interface: %s\n", strerror(errno)); |
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goto failed; |
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} |
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dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES, |
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PROT_READ, MAP_PRIVATE, dv->fd, 0); |
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if (dv->ring == MAP_FAILED) { |
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av_log(context, AV_LOG_ERROR, "Failed to mmap DV ring buffer: %s\n", strerror(errno)); |
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goto failed; |
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} |
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if (dv1394_start(dv) < 0) |
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goto failed; |
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return 0; |
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failed: |
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close(dv->fd); |
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return AVERROR(EIO); |
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} |
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static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt) |
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{ |
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struct dv1394_data *dv = context->priv_data; |
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int size; |
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size = avpriv_dv_get_packet(dv->dv_demux, pkt); |
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if (size > 0) |
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return size; |
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if (!dv->avail) { |
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struct dv1394_status s; |
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struct pollfd p; |
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if (dv->done) { |
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/* Request more frames */ |
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if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) { |
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/* This usually means that ring buffer overflowed.
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* We have to reset :(. |
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*/ |
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av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n"); |
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dv1394_reset(dv); |
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dv1394_start(dv); |
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} |
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dv->done = 0; |
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} |
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/* Wait until more frames are available */ |
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restart_poll: |
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p.fd = dv->fd; |
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p.events = POLLIN | POLLERR | POLLHUP; |
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if (poll(&p, 1, -1) < 0) { |
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if (errno == EAGAIN || errno == EINTR) |
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goto restart_poll; |
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av_log(context, AV_LOG_ERROR, "Poll failed: %s\n", strerror(errno)); |
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return AVERROR(EIO); |
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} |
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if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) { |
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av_log(context, AV_LOG_ERROR, "Failed to get status: %s\n", strerror(errno)); |
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return AVERROR(EIO); |
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} |
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av_log(context, AV_LOG_TRACE, "DV1394: status\n" |
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"\tactive_frame\t%d\n" |
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"\tfirst_clear_frame\t%d\n" |
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"\tn_clear_frames\t%d\n" |
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"\tdropped_frames\t%d\n", |
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s.active_frame, s.first_clear_frame, |
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s.n_clear_frames, s.dropped_frames); |
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dv->avail = s.n_clear_frames; |
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dv->index = s.first_clear_frame; |
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dv->done = 0; |
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if (s.dropped_frames) { |
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av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n", |
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s.dropped_frames); |
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dv1394_reset(dv); |
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dv1394_start(dv); |
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} |
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} |
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av_log(context, AV_LOG_TRACE, "index %d, avail %d, done %d\n", dv->index, dv->avail, |
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dv->done); |
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size = avpriv_dv_produce_packet(dv->dv_demux, pkt, |
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dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE), |
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DV1394_PAL_FRAME_SIZE); |
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dv->index = (dv->index + 1) % DV1394_RING_FRAMES; |
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dv->done++; dv->avail--; |
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return size; |
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} |
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static int dv1394_close(AVFormatContext * context) |
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{ |
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struct dv1394_data *dv = context->priv_data; |
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/* Shutdown DV1394 receiver */ |
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if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0) |
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av_log(context, AV_LOG_ERROR, "Failed to shutdown DV1394: %s\n", strerror(errno)); |
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/* Unmap ring buffer */ |
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if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0) |
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av_log(context, AV_LOG_ERROR, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno)); |
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close(dv->fd); |
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av_free(dv->dv_demux); |
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return 0; |
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} |
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static const AVOption options[] = { |
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{ "standard", "", offsetof(struct dv1394_data, format), AV_OPT_TYPE_INT, {.i64 = DV1394_NTSC}, DV1394_NTSC, DV1394_PAL, AV_OPT_FLAG_DECODING_PARAM, "standard" }, |
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{ "PAL", "", 0, AV_OPT_TYPE_CONST, {.i64 = DV1394_PAL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, |
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{ "NTSC", "", 0, AV_OPT_TYPE_CONST, {.i64 = DV1394_NTSC}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" }, |
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{ "channel", "", offsetof(struct dv1394_data, channel), AV_OPT_TYPE_INT, {.i64 = DV1394_DEFAULT_CHANNEL}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM }, |
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{ NULL }, |
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}; |
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static const AVClass dv1394_class = { |
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.class_name = "DV1394 indev", |
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.item_name = av_default_item_name, |
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.option = options, |
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.version = LIBAVUTIL_VERSION_INT, |
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}; |
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AVInputFormat ff_dv1394_demuxer = { |
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.name = "dv1394", |
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.long_name = NULL_IF_CONFIG_SMALL("DV1394 A/V grab"), |
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.priv_data_size = sizeof(struct dv1394_data), |
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.read_header = dv1394_read_header, |
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.read_packet = dv1394_read_packet, |
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.read_close = dv1394_close, |
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.flags = AVFMT_NOFILE, |
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.priv_class = &dv1394_class, |
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}; |
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@ -1,357 +0,0 @@ |
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/*
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* DV input/output over IEEE 1394 on OHCI chips |
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* Copyright (C)2001 Daniel Maas <dmaas@dcine.com> |
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* receive, proc_fs by Dan Dennedy <dan@dennedy.org> |
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* |
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* based on: |
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* video1394.h - driver for OHCI 1394 boards |
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* Copyright (C)1999,2000 Sebastien Rougeaux <sebastien.rougeaux@anu.edu.au> |
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* Peter Schlaile <udbz@rz.uni-karlsruhe.de> |
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* |
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* This file is part of Libav. |
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* |
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* Libav is free software; you can redistribute it and/or |
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* modify it under the terms of the GNU Lesser General Public |
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* License as published by the Free Software Foundation; either |
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* version 2.1 of the License, or (at your option) any later version. |
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* |
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* Libav is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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* Lesser General Public License for more details. |
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* |
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* You should have received a copy of the GNU Lesser General Public |
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* License along with Libav; if not, write to the Free Software |
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
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*/ |
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#ifndef AVDEVICE_DV1394_H |
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#define AVDEVICE_DV1394_H |
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#define DV1394_DEFAULT_CHANNEL 63 |
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#define DV1394_DEFAULT_CARD 0 |
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#define DV1394_RING_FRAMES 20 |
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#define DV1394_WIDTH 720 |
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#define DV1394_NTSC_HEIGHT 480 |
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#define DV1394_PAL_HEIGHT 576 |
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/* This is the public user-space interface. Try not to break it. */ |
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#define DV1394_API_VERSION 0x20011127 |
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/* ********************
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** ** |
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** DV1394 API ** |
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** ** |
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******************** |
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There are two methods of operating the DV1394 DV output device. |
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1) |
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The simplest is an interface based on write(): simply write |
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full DV frames of data to the device, and they will be transmitted |
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as quickly as possible. The FD may be set for non-blocking I/O, |
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in which case you can use select() or poll() to wait for output |
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buffer space. |
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To set the DV output parameters (e.g. whether you want NTSC or PAL |
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video), use the DV1394_INIT ioctl, passing in the parameters you |
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want in a struct dv1394_init. |
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Example 1: |
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To play a raw .DV file: cat foo.DV > /dev/dv1394 |
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(cat will use write() internally) |
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Example 2: |
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static struct dv1394_init init = { |
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0x63, (broadcast channel) |
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4, (four-frame ringbuffer) |
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DV1394_NTSC, (send NTSC video) |
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0, 0 (default empty packet rate) |
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} |
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ioctl(fd, DV1394_INIT, &init); |
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while(1) { |
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read( <a raw DV file>, buf, DV1394_NTSC_FRAME_SIZE ); |
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write( <the dv1394 FD>, buf, DV1394_NTSC_FRAME_SIZE ); |
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} |
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2) |
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For more control over buffering, and to avoid unnecessary copies |
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of the DV data, you can use the more sophisticated the mmap() interface. |
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First, call the DV1394_INIT ioctl to specify your parameters, |
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including the number of frames in the ringbuffer. Then, calling mmap() |
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on the dv1394 device will give you direct access to the ringbuffer |
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from which the DV card reads your frame data. |
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The ringbuffer is simply one large, contiguous region of memory |
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containing two or more frames of packed DV data. Each frame of DV data |
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is 120000 bytes (NTSC) or 144000 bytes (PAL). |
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Fill one or more frames in the ringbuffer, then use the DV1394_SUBMIT_FRAMES |
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ioctl to begin I/O. You can use either the DV1394_WAIT_FRAMES ioctl |
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or select()/poll() to wait until the frames are transmitted. Next, you'll |
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need to call the DV1394_GET_STATUS ioctl to determine which ringbuffer |
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frames are clear (ready to be filled with new DV data). Finally, use |
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DV1394_SUBMIT_FRAMES again to send the new data to the DV output. |
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Example: here is what a four-frame ringbuffer might look like |
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during DV transmission: |
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frame 0 frame 1 frame 2 frame 3 |
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*--------------------------------------* |
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| CLEAR | DV data | DV data | CLEAR | |
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*--------------------------------------* |
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<ACTIVE> |
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transmission goes in this direction --->>> |
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The DV hardware is currently transmitting the data in frame 1. |
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Once frame 1 is finished, it will automatically transmit frame 2. |
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(if frame 2 finishes before frame 3 is submitted, the device |
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will continue to transmit frame 2, and will increase the dropped_frames |
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counter each time it repeats the transmission). |
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|
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|
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If you called DV1394_GET_STATUS at this instant, you would |
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receive the following values: |
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n_frames = 4 |
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active_frame = 1 |
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first_clear_frame = 3 |
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n_clear_frames = 2 |
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|
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At this point, you should write new DV data into frame 3 and optionally |
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frame 0. Then call DV1394_SUBMIT_FRAMES to inform the device that |
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it may transmit the new frames. |
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|
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ERROR HANDLING |
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|
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An error (buffer underflow/overflow or a break in the DV stream due |
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to a 1394 bus reset) can be detected by checking the dropped_frames |
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field of struct dv1394_status (obtained through the |
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DV1394_GET_STATUS ioctl). |
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|
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The best way to recover from such an error is to re-initialize |
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dv1394, either by using the DV1394_INIT ioctl call, or closing the |
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file descriptor and opening it again. (note that you must unmap all |
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ringbuffer mappings when closing the file descriptor, or else |
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dv1394 will still be considered 'in use'). |
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|
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MAIN LOOP |
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|
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For maximum efficiency and robustness against bus errors, you are |
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advised to model the main loop of your application after the |
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following pseudo-code example: |
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|
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(checks of system call return values omitted for brevity; always |
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check return values in your code!) |
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|
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while( frames left ) { |
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|
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struct pollfd *pfd = ...; |
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|
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pfd->fd = dv1394_fd; |
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pfd->revents = 0; |
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pfd->events = POLLOUT | POLLIN; (OUT for transmit, IN for receive) |
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|
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(add other sources of I/O here) |
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|
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poll(pfd, 1, -1); (or select(); add a timeout if you want) |
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|
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if(pfd->revents) { |
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struct dv1394_status status; |
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|
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ioctl(dv1394_fd, DV1394_GET_STATUS, &status); |
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|
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if(status.dropped_frames > 0) { |
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reset_dv1394(); |
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} else { |
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int i; |
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for (i = 0; i < status.n_clear_frames; i++) { |
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copy_DV_frame(); |
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} |
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} |
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} |
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} |
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|
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where copy_DV_frame() reads or writes on the dv1394 file descriptor |
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(read/write mode) or copies data to/from the mmap ringbuffer and |
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then calls ioctl(DV1394_SUBMIT_FRAMES) to notify dv1394 that new |
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frames are available (mmap mode). |
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|
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reset_dv1394() is called in the event of a buffer |
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underflow/overflow or a halt in the DV stream (e.g. due to a 1394 |
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bus reset). To guarantee recovery from the error, this function |
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should close the dv1394 file descriptor (and munmap() all |
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ringbuffer mappings, if you are using them), then re-open the |
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dv1394 device (and re-map the ringbuffer). |
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|
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*/ |
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|
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|
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/* maximum number of frames in the ringbuffer */ |
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#define DV1394_MAX_FRAMES 32 |
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|
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/* number of *full* isochronous packets per DV frame */ |
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#define DV1394_NTSC_PACKETS_PER_FRAME 250 |
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#define DV1394_PAL_PACKETS_PER_FRAME 300 |
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|
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/* size of one frame's worth of DV data, in bytes */ |
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#define DV1394_NTSC_FRAME_SIZE (480 * DV1394_NTSC_PACKETS_PER_FRAME) |
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#define DV1394_PAL_FRAME_SIZE (480 * DV1394_PAL_PACKETS_PER_FRAME) |
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|
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|
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/* ioctl() commands */ |
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|
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enum { |
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/* I don't like using 0 as a valid ioctl() */ |
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DV1394_INVALID = 0, |
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|
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|
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/* get the driver ready to transmit video.
|
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pass a struct dv1394_init* as the parameter (see below), |
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or NULL to get default parameters */ |
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DV1394_INIT, |
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|
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|
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/* stop transmitting video and free the ringbuffer */ |
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DV1394_SHUTDOWN, |
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|
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|
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/* submit N new frames to be transmitted, where
|
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the index of the first new frame is first_clear_buffer, |
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and the index of the last new frame is |
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(first_clear_buffer + N) % n_frames */ |
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DV1394_SUBMIT_FRAMES, |
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|
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|
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/* block until N buffers are clear (pass N as the parameter)
|
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Because we re-transmit the last frame on underrun, there |
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will at most be n_frames - 1 clear frames at any time */ |
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DV1394_WAIT_FRAMES, |
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|
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/* capture new frames that have been received, where
|
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the index of the first new frame is first_clear_buffer, |
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and the index of the last new frame is |
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(first_clear_buffer + N) % n_frames */ |
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DV1394_RECEIVE_FRAMES, |
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|
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|
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DV1394_START_RECEIVE, |
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|
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|
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/* pass a struct dv1394_status* as the parameter (see below) */ |
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DV1394_GET_STATUS, |
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}; |
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|
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|
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|
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enum pal_or_ntsc { |
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DV1394_NTSC = 0, |
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DV1394_PAL |
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}; |
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|
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|
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|
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|
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/* this is the argument to DV1394_INIT */ |
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struct dv1394_init { |
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/* DV1394_API_VERSION */ |
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unsigned int api_version; |
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|
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/* isochronous transmission channel to use */ |
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unsigned int channel; |
||||
|
||||
/* number of frames in the ringbuffer. Must be at least 2
|
||||
and at most DV1394_MAX_FRAMES. */ |
||||
unsigned int n_frames; |
||||
|
||||
/* send/receive PAL or NTSC video format */ |
||||
enum pal_or_ntsc format; |
||||
|
||||
/* the following are used only for transmission */ |
||||
|
||||
/* set these to zero unless you want a
|
||||
non-default empty packet rate (see below) */ |
||||
unsigned long cip_n; |
||||
unsigned long cip_d; |
||||
|
||||
/* set this to zero unless you want a
|
||||
non-default SYT cycle offset (default = 3 cycles) */ |
||||
unsigned int syt_offset; |
||||
}; |
||||
|
||||
/* NOTE: you may only allocate the DV frame ringbuffer once each time
|
||||
you open the dv1394 device. DV1394_INIT will fail if you call it a |
||||
second time with different 'n_frames' or 'format' arguments (which |
||||
would imply a different size for the ringbuffer). If you need a |
||||
different buffer size, simply close and re-open the device, then |
||||
initialize it with your new settings. */ |
||||
|
||||
/* Q: What are cip_n and cip_d? */ |
||||
|
||||
/*
|
||||
A: DV video streams do not utilize 100% of the potential bandwidth offered |
||||
by IEEE 1394 (FireWire). To achieve the correct rate of data transmission, |
||||
DV devices must periodically insert empty packets into the 1394 data stream. |
||||
Typically there is one empty packet per 14-16 data-carrying packets. |
||||
|
||||
Some DV devices will accept a wide range of empty packet rates, while others |
||||
require a precise rate. If the dv1394 driver produces empty packets at |
||||
a rate that your device does not accept, you may see ugly patterns on the |
||||
DV output, or even no output at all. |
||||
|
||||
The default empty packet insertion rate seems to work for many people; if |
||||
your DV output is stable, you can simply ignore this discussion. However, |
||||
we have exposed the empty packet rate as a parameter to support devices that |
||||
do not work with the default rate. |
||||
|
||||
The decision to insert an empty packet is made with a numerator/denominator |
||||
algorithm. Empty packets are produced at an average rate of CIP_N / CIP_D. |
||||
You can alter the empty packet rate by passing non-zero values for cip_n |
||||
and cip_d to the INIT ioctl. |
||||
|
||||
*/ |
||||
|
||||
|
||||
|
||||
struct dv1394_status { |
||||
/* this embedded init struct returns the current dv1394
|
||||
parameters in use */ |
||||
struct dv1394_init init; |
||||
|
||||
/* the ringbuffer frame that is currently being
|
||||
displayed. (-1 if the device is not transmitting anything) */ |
||||
int active_frame; |
||||
|
||||
/* index of the first buffer (ahead of active_frame) that
|
||||
is ready to be filled with data */ |
||||
unsigned int first_clear_frame; |
||||
|
||||
/* how many buffers, including first_clear_buffer, are
|
||||
ready to be filled with data */ |
||||
unsigned int n_clear_frames; |
||||
|
||||
/* how many times the DV stream has underflowed, overflowed,
|
||||
or otherwise encountered an error, since the previous call |
||||
to DV1394_GET_STATUS */ |
||||
unsigned int dropped_frames; |
||||
|
||||
/* N.B. The dropped_frames counter is only a lower bound on the actual
|
||||
number of dropped frames, with the special case that if dropped_frames |
||||
is zero, then it is guaranteed that NO frames have been dropped |
||||
since the last call to DV1394_GET_STATUS. |
||||
*/ |
||||
}; |
||||
|
||||
|
||||
#endif /* AVDEVICE_DV1394_H */ |
||||
Loading…
Reference in new issue