2 * Linux DV1394 interface
3 * Copyright (c) 2003 Max Krasnyansky <maxk@qualcomm.com>
5 * This file is part of FFmpeg.
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.
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.
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
27 #include <sys/ioctl.h>
30 #include "libavutil/internal.h"
31 #include "libavutil/log.h"
32 #include "libavutil/opt.h"
34 #include "libavformat/dv.h"
43 uint8_t *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 DVDemuxContext
* dv_demux
; /* Generic DV muxing/demuxing context */
52 * The trick here is to kludge around well known problem with kernel Ooopsing
53 * when you try to capture PAL on a device node configure for NTSC. That's
54 * why we have to configure the device node for PAL, and then read only NTSC
57 static int dv1394_reset(struct dv1394_data
*dv
)
59 struct dv1394_init init
;
61 init
.channel
= dv
->channel
;
62 init
.api_version
= DV1394_API_VERSION
;
63 init
.n_frames
= DV1394_RING_FRAMES
;
64 init
.format
= DV1394_PAL
;
66 if (ioctl(dv
->fd
, DV1394_INIT
, &init
) < 0)
69 dv
->avail
= dv
->done
= 0;
73 static int dv1394_start(struct dv1394_data
*dv
)
75 /* Tell DV1394 driver to enable receiver */
76 if (ioctl(dv
->fd
, DV1394_START_RECEIVE
, 0) < 0) {
77 av_log(NULL
, AV_LOG_ERROR
, "Failed to start receiver: %s\n", strerror(errno
));
83 static int dv1394_read_header(AVFormatContext
* context
)
85 struct dv1394_data
*dv
= context
->priv_data
;
87 dv
->dv_demux
= avpriv_dv_init_demux(context
);
91 /* Open and initialize DV1394 device */
92 dv
->fd
= avpriv_open(context
->filename
, O_RDONLY
);
94 av_log(context
, AV_LOG_ERROR
, "Failed to open DV interface: %s\n", strerror(errno
));
98 if (dv1394_reset(dv
) < 0) {
99 av_log(context
, AV_LOG_ERROR
, "Failed to initialize DV interface: %s\n", strerror(errno
));
103 dv
->ring
= mmap(NULL
, DV1394_PAL_FRAME_SIZE
* DV1394_RING_FRAMES
,
104 PROT_READ
, MAP_PRIVATE
, dv
->fd
, 0);
105 if (dv
->ring
== MAP_FAILED
) {
106 av_log(context
, AV_LOG_ERROR
, "Failed to mmap DV ring buffer: %s\n", strerror(errno
));
110 if (dv1394_start(dv
) < 0)
120 static int dv1394_read_packet(AVFormatContext
*context
, AVPacket
*pkt
)
122 struct dv1394_data
*dv
= context
->priv_data
;
125 size
= avpriv_dv_get_packet(dv
->dv_demux
, pkt
);
130 struct dv1394_status s
;
134 /* Request more frames */
135 if (ioctl(dv
->fd
, DV1394_RECEIVE_FRAMES
, dv
->done
) < 0) {
136 /* This usually means that ring buffer overflowed.
137 * We have to reset :(.
140 av_log(context
, AV_LOG_ERROR
, "DV1394: Ring buffer overflow. Reseting ..\n");
148 /* Wait until more frames are available */
151 p
.events
= POLLIN
| POLLERR
| POLLHUP
;
152 if (poll(&p
, 1, -1) < 0) {
153 if (errno
== EAGAIN
|| errno
== EINTR
)
155 av_log(context
, AV_LOG_ERROR
, "Poll failed: %s\n", strerror(errno
));
159 if (ioctl(dv
->fd
, DV1394_GET_STATUS
, &s
) < 0) {
160 av_log(context
, AV_LOG_ERROR
, "Failed to get status: %s\n", strerror(errno
));
163 av_dlog(context
, "DV1394: status\n"
164 "\tactive_frame\t%d\n"
165 "\tfirst_clear_frame\t%d\n"
166 "\tn_clear_frames\t%d\n"
167 "\tdropped_frames\t%d\n",
168 s
.active_frame
, s
.first_clear_frame
,
169 s
.n_clear_frames
, s
.dropped_frames
);
171 dv
->avail
= s
.n_clear_frames
;
172 dv
->index
= s
.first_clear_frame
;
175 if (s
.dropped_frames
) {
176 av_log(context
, AV_LOG_ERROR
, "DV1394: Frame drop detected (%d). Reseting ..\n",
184 av_dlog(context
, "index %d, avail %d, done %d\n", dv
->index
, dv
->avail
,
187 size
= avpriv_dv_produce_packet(dv
->dv_demux
, pkt
,
188 dv
->ring
+ (dv
->index
* DV1394_PAL_FRAME_SIZE
),
189 DV1394_PAL_FRAME_SIZE
, -1);
190 dv
->index
= (dv
->index
+ 1) % DV1394_RING_FRAMES
;
191 dv
->done
++; dv
->avail
--;
196 static int dv1394_close(AVFormatContext
* context
)
198 struct dv1394_data
*dv
= context
->priv_data
;
200 /* Shutdown DV1394 receiver */
201 if (ioctl(dv
->fd
, DV1394_SHUTDOWN
, 0) < 0)
202 av_log(context
, AV_LOG_ERROR
, "Failed to shutdown DV1394: %s\n", strerror(errno
));
204 /* Unmap ring buffer */
205 if (munmap(dv
->ring
, DV1394_NTSC_FRAME_SIZE
* DV1394_RING_FRAMES
) < 0)
206 av_log(context
, AV_LOG_ERROR
, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno
));
209 av_free(dv
->dv_demux
);
214 static const AVOption options
[] = {
215 { "standard", "", offsetof(struct dv1394_data
, format
), AV_OPT_TYPE_INT
, {.i64
= DV1394_NTSC
}, DV1394_NTSC
, DV1394_PAL
, AV_OPT_FLAG_DECODING_PARAM
, "standard" },
216 { "PAL", "", 0, AV_OPT_TYPE_CONST
, {.i64
= DV1394_PAL
}, 0, 0, AV_OPT_FLAG_DECODING_PARAM
, "standard" },
217 { "NTSC", "", 0, AV_OPT_TYPE_CONST
, {.i64
= DV1394_NTSC
}, 0, 0, AV_OPT_FLAG_DECODING_PARAM
, "standard" },
218 { "channel", "", offsetof(struct dv1394_data
, channel
), AV_OPT_TYPE_INT
, {.i64
= DV1394_DEFAULT_CHANNEL
}, 0, INT_MAX
, AV_OPT_FLAG_DECODING_PARAM
},
222 static const AVClass dv1394_class
= {
223 .class_name
= "DV1394 indev",
224 .item_name
= av_default_item_name
,
226 .version
= LIBAVUTIL_VERSION_INT
,
227 .category
= AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT
,
230 AVInputFormat ff_dv1394_demuxer
= {
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 .priv_class
= &dv1394_class
,