mirror of https://github.com/FFmpeg/FFmpeg.git
Originally committed as revision 1493 to svn://svn.ffmpeg.org/ffmpeg/trunkpull/126/head
Max Krasnyansky
22 years ago
committed by
Fabrice Bellard
parent
4b8b2edb62
commit
8aa3ee32c2
7 changed files with 648 additions and 12 deletions
@ -0,0 +1,249 @@ |
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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 library 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 of the License, or (at your option) any later version. |
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* |
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* This library 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 this library; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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#include <unistd.h> |
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#include <fcntl.h> |
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#include <sys/ioctl.h> |
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#include <sys/mman.h> |
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#include <sys/poll.h> |
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#include <sys/time.h> |
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#include <time.h> |
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#include "avformat.h" |
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#undef DV1394_DEBUG |
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#include "dv1394.h" |
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int dv1394_channel = DV1394_DEFAULT_CHANNEL; |
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struct dv1394_data { |
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int fd; |
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int channel; |
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int width, height; |
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int frame_rate; |
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int frame_size; |
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void *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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}; |
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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_NTSC; |
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if (ioctl(dv->fd, DV1394_INIT, &init) < 0) |
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return -1; |
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dv->avail = 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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perror("Failed to start receiver"); |
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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, AVFormatParameters * ap) |
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{ |
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struct dv1394_data *dv = context->priv_data; |
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AVStream *st; |
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st = av_new_stream(context, 0); |
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if (!st) |
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return -ENOMEM; |
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dv->width = DV1394_WIDTH; |
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dv->height = DV1394_HEIGHT; |
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dv->channel = dv1394_channel; |
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dv->frame_rate = 30; |
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dv->frame_size = DV1394_NTSC_FRAME_SIZE; |
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/* Open and initialize DV1394 device */ |
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dv->fd = open(video_device, O_RDONLY); |
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if (dv->fd < 0) { |
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perror("Failed to open DV interface"); |
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goto failed; |
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} |
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if (dv1394_reset(dv) < 0) { |
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perror("Failed to initialize DV interface"); |
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goto failed; |
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} |
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dv->ring = mmap(NULL, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES, |
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PROT_READ, MAP_PRIVATE, dv->fd, 0); |
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if (!dv->ring) { |
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perror("Failed to mmap DV ring buffer"); |
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goto failed; |
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} |
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st->codec.codec_type = CODEC_TYPE_VIDEO; |
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st->codec.codec_id = CODEC_ID_DVVIDEO; |
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st->codec.width = dv->width; |
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st->codec.height = dv->height; |
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st->codec.frame_rate = dv->frame_rate * FRAME_RATE_BASE; |
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st->codec.bit_rate = 25000000; /* Consumer DV is 25Mbps */ |
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av_set_pts_info(context, 48, 1, 1000000); |
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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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av_free(st); |
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return -EIO; |
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} |
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static inline int __copy_frame(struct dv1394_data *dv, void *buf) |
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{ |
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char *ptr = dv->ring + (dv->index * dv->frame_size); |
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memcpy(buf, ptr, dv->frame_size); |
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dv->index = (dv->index + 1) % DV1394_RING_FRAMES; |
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dv->avail--; |
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dv->done++; |
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return dv->frame_size; |
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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 len; |
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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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p.fd = dv->fd; |
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p.events = POLLIN | POLLERR | POLLHUP; |
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/* Wait until more frames are available */ |
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if (poll(&p, 1, -1) < 0) { |
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perror("Poll failed"); |
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return -EIO; |
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} |
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if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) { |
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perror("Failed to get status"); |
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return -EIO; |
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} |
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#ifdef DV1394_DEBUG |
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fprintf(stderr, "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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#endif |
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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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fprintf(stderr, "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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if (av_new_packet(pkt, dv->frame_size) < 0) |
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return -EIO; |
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#ifdef DV1394_DEBUG |
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fprintf(stderr, "index %d, avail %d, done %d\n", dv->index, dv->avail, |
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dv->done); |
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#endif |
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len = __copy_frame(dv, pkt->data); |
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pkt->pts = av_gettime() & ((1LL << 48) - 1); |
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if (!dv->avail && 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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fprintf(stderr, "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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} |
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return len; |
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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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perror("Failed to shutdown DV1394"); |
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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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perror("Failed to munmap DV1394 ring buffer"); |
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close(dv->fd); |
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return 0; |
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} |
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static AVInputFormat dv1394_format = { |
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.name = "dv1394", |
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.long_name = "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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}; |
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int dv1394_init(void) |
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{ |
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av_register_input_format(&dv1394_format); |
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return 0; |
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} |
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@ -0,0 +1,353 @@ |
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/*
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* dv1394.h - 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 program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program 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 |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software Foundation, |
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* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
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*/ |
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#ifndef _DV_1394_H |
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#define _DV_1394_H |
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#define DV1394_DEFAULT_CHANNEL 0x63 |
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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_HEIGHT 480 |
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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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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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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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ERROR HANDLING |
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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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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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MAIN LOOP |
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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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(checks of system call return values omitted for brevity; always |
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check return values in your code!) |
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while( frames left ) { |
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struct pollfd *pfd = ...; |
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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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(add other sources of I/O here) |
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poll(pfd, 1, -1); (or select(); add a timeout if you want) |
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if(pfd->revents) { |
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struct dv1394_status status; |
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ioctl(dv1394_fd, DV1394_GET_STATUS, &status); |
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if(status.dropped_frames > 0) { |
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reset_dv1394(); |
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} else { |
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for(int 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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} |
||||||
|
} |
||||||
|
|
||||||
|
where copy_DV_frame() reads or writes on the dv1394 file descriptor |
||||||
|
(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 |
||||||
|
frames are availble (mmap mode). |
||||||
|
|
||||||
|
reset_dv1394() is called in the event of a buffer |
||||||
|
underflow/overflow or a halt in the DV stream (e.g. due to a 1394 |
||||||
|
bus reset). To guarantee recovery from the error, this function |
||||||
|
should close the dv1394 file descriptor (and munmap() all |
||||||
|
ringbuffer mappings, if you are using them), then re-open the |
||||||
|
dv1394 device (and re-map the ringbuffer). |
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|
|
||||||
|
*/ |
||||||
|
|
||||||
|
|
||||||
|
/* maximum number of frames in the ringbuffer */ |
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|
#define DV1394_MAX_FRAMES 32 |
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|
|
||||||
|
/* number of *full* isochronous packets per DV frame */ |
||||||
|
#define DV1394_NTSC_PACKETS_PER_FRAME 250 |
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|
#define DV1394_PAL_PACKETS_PER_FRAME 300 |
||||||
|
|
||||||
|
/* size of one frame's worth of DV data, in bytes */ |
||||||
|
#define DV1394_NTSC_FRAME_SIZE (480 * DV1394_NTSC_PACKETS_PER_FRAME) |
||||||
|
#define DV1394_PAL_FRAME_SIZE (480 * DV1394_PAL_PACKETS_PER_FRAME) |
||||||
|
|
||||||
|
|
||||||
|
/* ioctl() commands */ |
||||||
|
|
||||||
|
enum { |
||||||
|
/* I don't like using 0 as a valid ioctl() */ |
||||||
|
DV1394_INVALID = 0, |
||||||
|
|
||||||
|
|
||||||
|
/* get the driver ready to transmit video.
|
||||||
|
pass a struct dv1394_init* as the parameter (see below), |
||||||
|
or NULL to get default parameters */ |
||||||
|
DV1394_INIT, |
||||||
|
|
||||||
|
|
||||||
|
/* stop transmitting video and free the ringbuffer */ |
||||||
|
DV1394_SHUTDOWN, |
||||||
|
|
||||||
|
|
||||||
|
/* submit N new frames to be transmitted, where
|
||||||
|
the index of the first new frame is first_clear_buffer, |
||||||
|
and the index of the last new frame is |
||||||
|
(first_clear_buffer + N) % n_frames */ |
||||||
|
DV1394_SUBMIT_FRAMES, |
||||||
|
|
||||||
|
|
||||||
|
/* block until N buffers are clear (pass N as the parameter)
|
||||||
|
Because we re-transmit the last frame on underrun, there |
||||||
|
will at most be n_frames - 1 clear frames at any time */ |
||||||
|
DV1394_WAIT_FRAMES, |
||||||
|
|
||||||
|
/* capture new frames that have been received, where
|
||||||
|
the index of the first new frame is first_clear_buffer, |
||||||
|
and the index of the last new frame is |
||||||
|
(first_clear_buffer + N) % n_frames */ |
||||||
|
DV1394_RECEIVE_FRAMES, |
||||||
|
|
||||||
|
|
||||||
|
DV1394_START_RECEIVE, |
||||||
|
|
||||||
|
|
||||||
|
/* pass a struct dv1394_status* as the parameter (see below) */ |
||||||
|
DV1394_GET_STATUS, |
||||||
|
}; |
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
enum pal_or_ntsc { |
||||||
|
DV1394_NTSC = 0, |
||||||
|
DV1394_PAL |
||||||
|
}; |
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
|
||||||
|
/* this is the argument to DV1394_INIT */ |
||||||
|
struct dv1394_init { |
||||||
|
/* DV1394_API_VERSION */ |
||||||
|
unsigned int api_version; |
||||||
|
|
||||||
|
/* isochronous transmission channel to use */ |
||||||
|
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 /* _DV_1394_H */ |
||||||
Loading…
Reference in new issue