2 * Linux DV1394 interface
3 * Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General Public
16 * License along with this library; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 #include <sys/ioctl.h>
43 void *ring; /* Ring buffer */
44 int index; /* Current frame index */
45 int avail; /* Number of frames available for reading */
46 int done; /* Number of completed frames */
48 int stream; /* Current stream. 0 - video, 1 - audio */
49 int64_t pts; /* Current timestamp */
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
59 static int dv1394_reset(struct dv1394_data *dv)
61 struct dv1394_init init;
63 init.channel = dv->channel;
64 init.api_version = DV1394_API_VERSION;
65 init.n_frames = DV1394_RING_FRAMES;
66 init.format = DV1394_PAL;
68 if (ioctl(dv->fd, DV1394_INIT, &init) < 0)
71 dv->avail = dv->done = 0;
76 static int dv1394_start(struct dv1394_data *dv)
78 /* Tell DV1394 driver to enable receiver */
79 if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) {
80 perror("Failed to start receiver");
86 static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap)
88 struct dv1394_data *dv = context->priv_data;
89 const char *video_device;
91 dv->vst = av_new_stream(context, 0);
94 dv->ast = av_new_stream(context, 1);
100 if (ap->standard && !strcasecmp(ap->standard, "pal"))
101 dv->format = DV1394_PAL;
103 dv->format = DV1394_NTSC;
106 dv->channel = ap->channel;
108 dv->channel = DV1394_DEFAULT_CHANNEL;
110 dv->width = DV1394_WIDTH;
111 if (dv->format == DV1394_NTSC) {
112 dv->height = DV1394_NTSC_HEIGHT;
113 dv->frame_size = DV1394_NTSC_FRAME_SIZE;
116 dv->height = DV1394_PAL_HEIGHT;
117 dv->frame_size = DV1394_PAL_FRAME_SIZE;
121 /* Open and initialize DV1394 device */
122 video_device = ap->device;
124 video_device = "/dev/dv1394/0";
125 dv->fd = open(video_device, O_RDONLY);
127 perror("Failed to open DV interface");
131 if (dv1394_reset(dv) < 0) {
132 perror("Failed to initialize DV interface");
136 dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES,
137 PROT_READ, MAP_PRIVATE, dv->fd, 0);
138 if (dv->ring == MAP_FAILED) {
139 perror("Failed to mmap DV ring buffer");
145 dv->vst->codec.codec_type = CODEC_TYPE_VIDEO;
146 dv->vst->codec.codec_id = CODEC_ID_DVVIDEO;
147 dv->vst->codec.width = dv->width;
148 dv->vst->codec.height = dv->height;
149 dv->vst->codec.frame_rate = dv->frame_rate;
150 dv->vst->codec.frame_rate_base = 1;
151 dv->vst->codec.bit_rate = 25000000; /* Consumer DV is 25Mbps */
153 dv->ast->codec.codec_type = CODEC_TYPE_AUDIO;
154 dv->ast->codec.codec_id = CODEC_ID_DVAUDIO;
155 dv->ast->codec.channels = 2;
156 dv->ast->codec.sample_rate= 48000;
158 av_set_pts_info(context, 48, 1, 1000000);
160 if (dv1394_start(dv) < 0)
172 static void __destruct_pkt(struct AVPacket *pkt)
174 pkt->data = NULL; pkt->size = 0;
178 static inline int __get_frame(struct dv1394_data *dv, AVPacket *pkt)
180 char *ptr = dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE);
183 dv->index = (dv->index + 1) % DV1394_RING_FRAMES;
184 dv->done++; dv->avail--;
186 dv->pts = av_gettime() & ((1LL << 48) - 1);
189 dv->format = ((ptr[3] & 0x80) == 0) ? DV1394_NTSC : DV1394_PAL;
190 if (dv->format == DV1394_NTSC) {
191 dv->frame_size = DV1394_NTSC_FRAME_SIZE;
192 dv->vst->codec.height = dv->height = DV1394_NTSC_HEIGHT;
193 dv->vst->codec.frame_rate = dv->frame_rate = 30;
195 dv->frame_size = DV1394_PAL_FRAME_SIZE;
196 dv->vst->codec.height = dv->height = DV1394_PAL_HEIGHT;
197 dv->vst->codec.frame_rate = dv->frame_rate = 25;
201 pkt->destruct = __destruct_pkt;
203 pkt->size = dv->frame_size;
205 pkt->stream_index = dv->stream;
206 pkt->flags |= PKT_FLAG_KEY;
210 return dv->frame_size;
213 static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt)
215 struct dv1394_data *dv = context->priv_data;
218 struct dv1394_status s;
222 /* Request more frames */
223 if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) {
224 /* This usually means that ring buffer overflowed.
225 * We have to reset :(.
228 fprintf(stderr, "DV1394: Ring buffer overflow. Reseting ..\n");
236 /* Wait until more frames are available */
239 p.events = POLLIN | POLLERR | POLLHUP;
240 if (poll(&p, 1, -1) < 0) {
241 if (errno == EAGAIN || errno == EINTR)
243 perror("Poll failed");
247 if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) {
248 perror("Failed to get status");
252 fprintf(stderr, "DV1394: status\n"
253 "\tactive_frame\t%d\n"
254 "\tfirst_clear_frame\t%d\n"
255 "\tn_clear_frames\t%d\n"
256 "\tdropped_frames\t%d\n",
257 s.active_frame, s.first_clear_frame,
258 s.n_clear_frames, s.dropped_frames);
261 dv->avail = s.n_clear_frames;
262 dv->index = s.first_clear_frame;
265 if (s.dropped_frames) {
266 fprintf(stderr, "DV1394: Frame drop detected (%d). Reseting ..\n",
275 fprintf(stderr, "index %d, avail %d, done %d\n", dv->index, dv->avail,
279 return __get_frame(dv, pkt);
282 static int dv1394_close(AVFormatContext * context)
284 struct dv1394_data *dv = context->priv_data;
286 /* Shutdown DV1394 receiver */
287 if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0)
288 perror("Failed to shutdown DV1394");
290 /* Unmap ring buffer */
291 if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0)
292 perror("Failed to munmap DV1394 ring buffer");
299 static AVInputFormat dv1394_format = {
301 .long_name = "dv1394 A/V grab",
302 .priv_data_size = sizeof(struct dv1394_data),
303 .read_header = dv1394_read_header,
304 .read_packet = dv1394_read_packet,
305 .read_close = dv1394_close,
306 .flags = AVFMT_NOFILE
309 int dv1394_init(void)
311 av_register_input_format(&dv1394_format);