1/* 2 * Linux DV1394 interface 3 * Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22#include "config.h" 23#include <unistd.h> 24#include <fcntl.h> 25#include <errno.h> 26#include <poll.h> 27#include <sys/ioctl.h> 28#include <sys/mman.h> 29#include <sys/time.h> 30#include <time.h> 31#include <strings.h> 32 33#include "libavformat/avformat.h" 34 35#undef DV1394_DEBUG 36 37#include "libavformat/dv.h" 38#include "dv1394.h" 39 40struct dv1394_data { 41 int fd; 42 int channel; 43 int format; 44 45 uint8_t *ring; /* Ring buffer */ 46 int index; /* Current frame index */ 47 int avail; /* Number of frames available for reading */ 48 int done; /* Number of completed frames */ 49 50 DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */ 51}; 52 53/* 54 * The trick here is to kludge around well known problem with kernel Ooopsing 55 * when you try to capture PAL on a device node configure for NTSC. That's 56 * why we have to configure the device node for PAL, and then read only NTSC 57 * amount of data. 58 */ 59static int dv1394_reset(struct dv1394_data *dv) 60{ 61 struct dv1394_init init; 62 63 init.channel = dv->channel; 64 init.api_version = DV1394_API_VERSION; 65 init.n_frames = DV1394_RING_FRAMES; 66 init.format = DV1394_PAL; 67 68 if (ioctl(dv->fd, DV1394_INIT, &init) < 0) 69 return -1; 70 71 dv->avail = dv->done = 0; 72 return 0; 73} 74 75static int dv1394_start(struct dv1394_data *dv) 76{ 77 /* Tell DV1394 driver to enable receiver */ 78 if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) { 79 av_log(NULL, AV_LOG_ERROR, "Failed to start receiver: %s\n", strerror(errno)); 80 return -1; 81 } 82 return 0; 83} 84 85static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap) 86{ 87 struct dv1394_data *dv = context->priv_data; 88 89 dv->dv_demux = dv_init_demux(context); 90 if (!dv->dv_demux) 91 goto failed; 92 93 if (ap->standard && !strcasecmp(ap->standard, "pal")) 94 dv->format = DV1394_PAL; 95 else 96 dv->format = DV1394_NTSC; 97 98 if (ap->channel) 99 dv->channel = ap->channel; 100 else 101 dv->channel = DV1394_DEFAULT_CHANNEL; 102 103 /* Open and initialize DV1394 device */ 104 dv->fd = open(context->filename, O_RDONLY); 105 if (dv->fd < 0) { 106 av_log(context, AV_LOG_ERROR, "Failed to open DV interface: %s\n", strerror(errno)); 107 goto failed; 108 } 109 110 if (dv1394_reset(dv) < 0) { 111 av_log(context, AV_LOG_ERROR, "Failed to initialize DV interface: %s\n", strerror(errno)); 112 goto failed; 113 } 114 115 dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES, 116 PROT_READ, MAP_PRIVATE, dv->fd, 0); 117 if (dv->ring == MAP_FAILED) { 118 av_log(context, AV_LOG_ERROR, "Failed to mmap DV ring buffer: %s\n", strerror(errno)); 119 goto failed; 120 } 121 122 if (dv1394_start(dv) < 0) 123 goto failed; 124 125 return 0; 126 127failed: 128 close(dv->fd); 129 return AVERROR(EIO); 130} 131 132static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt) 133{ 134 struct dv1394_data *dv = context->priv_data; 135 int size; 136 137 size = dv_get_packet(dv->dv_demux, pkt); 138 if (size > 0) 139 return size; 140 141 if (!dv->avail) { 142 struct dv1394_status s; 143 struct pollfd p; 144 145 if (dv->done) { 146 /* Request more frames */ 147 if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) { 148 /* This usually means that ring buffer overflowed. 149 * We have to reset :(. 150 */ 151 152 av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n"); 153 154 dv1394_reset(dv); 155 dv1394_start(dv); 156 } 157 dv->done = 0; 158 } 159 160 /* Wait until more frames are available */ 161restart_poll: 162 p.fd = dv->fd; 163 p.events = POLLIN | POLLERR | POLLHUP; 164 if (poll(&p, 1, -1) < 0) { 165 if (errno == EAGAIN || errno == EINTR) 166 goto restart_poll; 167 av_log(context, AV_LOG_ERROR, "Poll failed: %s\n", strerror(errno)); 168 return AVERROR(EIO); 169 } 170 171 if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) { 172 av_log(context, AV_LOG_ERROR, "Failed to get status: %s\n", strerror(errno)); 173 return AVERROR(EIO); 174 } 175#ifdef DV1394_DEBUG 176 av_log(context, AV_LOG_DEBUG, "DV1394: status\n" 177 "\tactive_frame\t%d\n" 178 "\tfirst_clear_frame\t%d\n" 179 "\tn_clear_frames\t%d\n" 180 "\tdropped_frames\t%d\n", 181 s.active_frame, s.first_clear_frame, 182 s.n_clear_frames, s.dropped_frames); 183#endif 184 185 dv->avail = s.n_clear_frames; 186 dv->index = s.first_clear_frame; 187 dv->done = 0; 188 189 if (s.dropped_frames) { 190 av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n", 191 s.dropped_frames); 192 193 dv1394_reset(dv); 194 dv1394_start(dv); 195 } 196 } 197 198#ifdef DV1394_DEBUG 199 av_log(context, AV_LOG_DEBUG, "index %d, avail %d, done %d\n", dv->index, dv->avail, 200 dv->done); 201#endif 202 203 size = dv_produce_packet(dv->dv_demux, pkt, 204 dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE), 205 DV1394_PAL_FRAME_SIZE); 206 dv->index = (dv->index + 1) % DV1394_RING_FRAMES; 207 dv->done++; dv->avail--; 208 209 return size; 210} 211 212static int dv1394_close(AVFormatContext * context) 213{ 214 struct dv1394_data *dv = context->priv_data; 215 216 /* Shutdown DV1394 receiver */ 217 if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0) 218 av_log(context, AV_LOG_ERROR, "Failed to shutdown DV1394: %s\n", strerror(errno)); 219 220 /* Unmap ring buffer */ 221 if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0) 222 av_log(context, AV_LOG_ERROR, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno)); 223 224 close(dv->fd); 225 av_free(dv->dv_demux); 226 227 return 0; 228} 229 230AVInputFormat dv1394_demuxer = { 231 .name = "dv1394", 232 .long_name = NULL_IF_CONFIG_SMALL("DV1394 A/V grab"), 233 .priv_data_size = sizeof(struct dv1394_data), 234 .read_header = dv1394_read_header, 235 .read_packet = dv1394_read_packet, 236 .read_close = dv1394_close, 237 .flags = AVFMT_NOFILE 238}; 239