fdf8428b5e8121f732929cc79d8d380ff6f37ba1
[libav.git] / libavdevice / dv1394.c
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 <sys/ioctl.h>
27 #include <sys/mman.h>
28 #include <sys/poll.h>
29 #include <sys/time.h>
30 #include <time.h>
31
32 #include "avformat.h"
33
34 #undef DV1394_DEBUG
35
36 #include "dv1394.h"
37 #include "dv.h"
38
39 struct dv1394_data {
40 int fd;
41 int channel;
42 int format;
43
44 uint8_t *ring; /* Ring buffer */
45 int index; /* Current frame index */
46 int avail; /* Number of frames available for reading */
47 int done; /* Number of completed frames */
48
49 DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */
50 };
51
52 /*
53 * The trick here is to kludge around well known problem with kernel Ooopsing
54 * when you try to capture PAL on a device node configure for NTSC. That's
55 * why we have to configure the device node for PAL, and then read only NTSC
56 * amount of data.
57 */
58 static int dv1394_reset(struct dv1394_data *dv)
59 {
60 struct dv1394_init init;
61
62 init.channel = dv->channel;
63 init.api_version = DV1394_API_VERSION;
64 init.n_frames = DV1394_RING_FRAMES;
65 init.format = DV1394_PAL;
66
67 if (ioctl(dv->fd, DV1394_INIT, &init) < 0)
68 return -1;
69
70 dv->avail = dv->done = 0;
71 return 0;
72 }
73
74 static int dv1394_start(struct dv1394_data *dv)
75 {
76 /* Tell DV1394 driver to enable receiver */
77 if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) {
78 av_log(NULL, AV_LOG_ERROR, "Failed to start receiver: %s\n", strerror(errno));
79 return -1;
80 }
81 return 0;
82 }
83
84 static int dv1394_read_header(AVFormatContext * context, AVFormatParameters * ap)
85 {
86 struct dv1394_data *dv = context->priv_data;
87
88 dv->dv_demux = dv_init_demux(context);
89 if (!dv->dv_demux)
90 goto failed;
91
92 if (ap->standard && !strcasecmp(ap->standard, "pal"))
93 dv->format = DV1394_PAL;
94 else
95 dv->format = DV1394_NTSC;
96
97 if (ap->channel)
98 dv->channel = ap->channel;
99 else
100 dv->channel = DV1394_DEFAULT_CHANNEL;
101
102 /* Open and initialize DV1394 device */
103 dv->fd = open(context->filename, O_RDONLY);
104 if (dv->fd < 0) {
105 av_log(context, AV_LOG_ERROR, "Failed to open DV interface: %s\n", strerror(errno));
106 goto failed;
107 }
108
109 if (dv1394_reset(dv) < 0) {
110 av_log(context, AV_LOG_ERROR, "Failed to initialize DV interface: %s\n", strerror(errno));
111 goto failed;
112 }
113
114 dv->ring = mmap(NULL, DV1394_PAL_FRAME_SIZE * DV1394_RING_FRAMES,
115 PROT_READ, MAP_PRIVATE, dv->fd, 0);
116 if (dv->ring == MAP_FAILED) {
117 av_log(context, AV_LOG_ERROR, "Failed to mmap DV ring buffer: %s\n", strerror(errno));
118 goto failed;
119 }
120
121 if (dv1394_start(dv) < 0)
122 goto failed;
123
124 return 0;
125
126 failed:
127 close(dv->fd);
128 return AVERROR(EIO);
129 }
130
131 static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt)
132 {
133 struct dv1394_data *dv = context->priv_data;
134 int size;
135
136 size = dv_get_packet(dv->dv_demux, pkt);
137 if (size > 0)
138 return size;
139
140 if (!dv->avail) {
141 struct dv1394_status s;
142 struct pollfd p;
143
144 if (dv->done) {
145 /* Request more frames */
146 if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) {
147 /* This usually means that ring buffer overflowed.
148 * We have to reset :(.
149 */
150
151 av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n");
152
153 dv1394_reset(dv);
154 dv1394_start(dv);
155 }
156 dv->done = 0;
157 }
158
159 /* Wait until more frames are available */
160 restart_poll:
161 p.fd = dv->fd;
162 p.events = POLLIN | POLLERR | POLLHUP;
163 if (poll(&p, 1, -1) < 0) {
164 if (errno == EAGAIN || errno == EINTR)
165 goto restart_poll;
166 av_log(context, AV_LOG_ERROR, "Poll failed: %s\n", strerror(errno));
167 return AVERROR(EIO);
168 }
169
170 if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) {
171 av_log(context, AV_LOG_ERROR, "Failed to get status: %s\n", strerror(errno));
172 return AVERROR(EIO);
173 }
174 #ifdef DV1394_DEBUG
175 av_log(context, AV_LOG_DEBUG, "DV1394: status\n"
176 "\tactive_frame\t%d\n"
177 "\tfirst_clear_frame\t%d\n"
178 "\tn_clear_frames\t%d\n"
179 "\tdropped_frames\t%d\n",
180 s.active_frame, s.first_clear_frame,
181 s.n_clear_frames, s.dropped_frames);
182 #endif
183
184 dv->avail = s.n_clear_frames;
185 dv->index = s.first_clear_frame;
186 dv->done = 0;
187
188 if (s.dropped_frames) {
189 av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n",
190 s.dropped_frames);
191
192 dv1394_reset(dv);
193 dv1394_start(dv);
194 }
195 }
196
197 #ifdef DV1394_DEBUG
198 av_log(context, AV_LOG_DEBUG, "index %d, avail %d, done %d\n", dv->index, dv->avail,
199 dv->done);
200 #endif
201
202 size = dv_produce_packet(dv->dv_demux, pkt,
203 dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE),
204 DV1394_PAL_FRAME_SIZE);
205 dv->index = (dv->index + 1) % DV1394_RING_FRAMES;
206 dv->done++; dv->avail--;
207
208 return size;
209 }
210
211 static int dv1394_close(AVFormatContext * context)
212 {
213 struct dv1394_data *dv = context->priv_data;
214
215 /* Shutdown DV1394 receiver */
216 if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0)
217 av_log(context, AV_LOG_ERROR, "Failed to shutdown DV1394: %s\n", strerror(errno));
218
219 /* Unmap ring buffer */
220 if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0)
221 av_log(context, AV_LOG_ERROR, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno));
222
223 close(dv->fd);
224 av_free(dv->dv_demux);
225
226 return 0;
227 }
228
229 AVInputFormat dv1394_demuxer = {
230 .name = "dv1394",
231 .long_name = "dv1394 A/V grab",
232 .priv_data_size = sizeof(struct dv1394_data),
233 .read_header = dv1394_read_header,
234 .read_packet = dv1394_read_packet,
235 .read_close = dv1394_close,
236 .flags = AVFMT_NOFILE
237 };