dv1394.c
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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 
30 #include "libavutil/log.h"
31 #include "libavutil/opt.h"
32 #include "avdevice.h"
33 #include "libavformat/dv.h"
34 #include "dv1394.h"
35 
36 struct dv1394_data {
37  AVClass *class;
38  int fd;
39  int channel;
40  int format;
41 
42  uint8_t *ring; /* Ring buffer */
43  int index; /* Current frame index */
44  int avail; /* Number of frames available for reading */
45  int done; /* Number of completed frames */
46 
47  DVDemuxContext* dv_demux; /* Generic DV muxing/demuxing context */
48 };
49 
50 /*
51  * The trick here is to kludge around well known problem with kernel Ooopsing
52  * when you try to capture PAL on a device node configure for NTSC. That's
53  * why we have to configure the device node for PAL, and then read only NTSC
54  * amount of data.
55  */
56 static int dv1394_reset(struct dv1394_data *dv)
57 {
58  struct dv1394_init init;
59 
60  init.channel = dv->channel;
63  init.format = DV1394_PAL;
64 
65  if (ioctl(dv->fd, DV1394_INIT, &init) < 0)
66  return -1;
67 
68  dv->avail = dv->done = 0;
69  return 0;
70 }
71 
72 static int dv1394_start(struct dv1394_data *dv)
73 {
74  /* Tell DV1394 driver to enable receiver */
75  if (ioctl(dv->fd, DV1394_START_RECEIVE, 0) < 0) {
76  av_log(NULL, AV_LOG_ERROR, "Failed to start receiver: %s\n", strerror(errno));
77  return -1;
78  }
79  return 0;
80 }
81 
82 static int dv1394_read_header(AVFormatContext * context)
83 {
84  struct dv1394_data *dv = context->priv_data;
85 
86  dv->dv_demux = avpriv_dv_init_demux(context);
87  if (!dv->dv_demux)
88  goto failed;
89 
90  /* Open and initialize DV1394 device */
91  dv->fd = open(context->filename, O_RDONLY);
92  if (dv->fd < 0) {
93  av_log(context, AV_LOG_ERROR, "Failed to open DV interface: %s\n", strerror(errno));
94  goto failed;
95  }
96 
97  if (dv1394_reset(dv) < 0) {
98  av_log(context, AV_LOG_ERROR, "Failed to initialize DV interface: %s\n", strerror(errno));
99  goto failed;
100  }
101 
103  PROT_READ, MAP_PRIVATE, dv->fd, 0);
104  if (dv->ring == MAP_FAILED) {
105  av_log(context, AV_LOG_ERROR, "Failed to mmap DV ring buffer: %s\n", strerror(errno));
106  goto failed;
107  }
108 
109  if (dv1394_start(dv) < 0)
110  goto failed;
111 
112  return 0;
113 
114 failed:
115  close(dv->fd);
116  return AVERROR(EIO);
117 }
118 
120 {
121  struct dv1394_data *dv = context->priv_data;
122  int size;
123 
124  size = avpriv_dv_get_packet(dv->dv_demux, pkt);
125  if (size > 0)
126  return size;
127 
128  if (!dv->avail) {
129  struct dv1394_status s;
130  struct pollfd p;
131 
132  if (dv->done) {
133  /* Request more frames */
134  if (ioctl(dv->fd, DV1394_RECEIVE_FRAMES, dv->done) < 0) {
135  /* This usually means that ring buffer overflowed.
136  * We have to reset :(.
137  */
138 
139  av_log(context, AV_LOG_ERROR, "DV1394: Ring buffer overflow. Reseting ..\n");
140 
141  dv1394_reset(dv);
142  dv1394_start(dv);
143  }
144  dv->done = 0;
145  }
146 
147  /* Wait until more frames are available */
148 restart_poll:
149  p.fd = dv->fd;
150  p.events = POLLIN | POLLERR | POLLHUP;
151  if (poll(&p, 1, -1) < 0) {
152  if (errno == EAGAIN || errno == EINTR)
153  goto restart_poll;
154  av_log(context, AV_LOG_ERROR, "Poll failed: %s\n", strerror(errno));
155  return AVERROR(EIO);
156  }
157 
158  if (ioctl(dv->fd, DV1394_GET_STATUS, &s) < 0) {
159  av_log(context, AV_LOG_ERROR, "Failed to get status: %s\n", strerror(errno));
160  return AVERROR(EIO);
161  }
162  av_dlog(context, "DV1394: status\n"
163  "\tactive_frame\t%d\n"
164  "\tfirst_clear_frame\t%d\n"
165  "\tn_clear_frames\t%d\n"
166  "\tdropped_frames\t%d\n",
169 
170  dv->avail = s.n_clear_frames;
171  dv->index = s.first_clear_frame;
172  dv->done = 0;
173 
174  if (s.dropped_frames) {
175  av_log(context, AV_LOG_ERROR, "DV1394: Frame drop detected (%d). Reseting ..\n",
176  s.dropped_frames);
177 
178  dv1394_reset(dv);
179  dv1394_start(dv);
180  }
181  }
182 
183  av_dlog(context, "index %d, avail %d, done %d\n", dv->index, dv->avail,
184  dv->done);
185 
186  size = avpriv_dv_produce_packet(dv->dv_demux, pkt,
187  dv->ring + (dv->index * DV1394_PAL_FRAME_SIZE),
189  dv->index = (dv->index + 1) % DV1394_RING_FRAMES;
190  dv->done++; dv->avail--;
191 
192  return size;
193 }
194 
195 static int dv1394_close(AVFormatContext * context)
196 {
197  struct dv1394_data *dv = context->priv_data;
198 
199  /* Shutdown DV1394 receiver */
200  if (ioctl(dv->fd, DV1394_SHUTDOWN, 0) < 0)
201  av_log(context, AV_LOG_ERROR, "Failed to shutdown DV1394: %s\n", strerror(errno));
202 
203  /* Unmap ring buffer */
204  if (munmap(dv->ring, DV1394_NTSC_FRAME_SIZE * DV1394_RING_FRAMES) < 0)
205  av_log(context, AV_LOG_ERROR, "Failed to munmap DV1394 ring buffer: %s\n", strerror(errno));
206 
207  close(dv->fd);
208  av_free(dv->dv_demux);
209 
210  return 0;
211 }
212 
213 static const AVOption options[] = {
214  { "standard", "", offsetof(struct dv1394_data, format), AV_OPT_TYPE_INT, {.i64 = DV1394_NTSC}, DV1394_NTSC, DV1394_PAL, AV_OPT_FLAG_DECODING_PARAM, "standard" },
215  { "PAL", "", 0, AV_OPT_TYPE_CONST, {.i64 = DV1394_PAL}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" },
216  { "NTSC", "", 0, AV_OPT_TYPE_CONST, {.i64 = DV1394_NTSC}, 0, 0, AV_OPT_FLAG_DECODING_PARAM, "standard" },
217  { "channel", "", offsetof(struct dv1394_data, channel), AV_OPT_TYPE_INT, {.i64 = DV1394_DEFAULT_CHANNEL}, 0, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
218  { NULL },
219 };
220 
221 static const AVClass dv1394_class = {
222  .class_name = "DV1394 indev",
223  .item_name = av_default_item_name,
224  .option = options,
225  .version = LIBAVUTIL_VERSION_INT,
226 };
227 
229  .name = "dv1394",
230  .long_name = NULL_IF_CONFIG_SMALL("DV1394 A/V grab"),
231  .priv_data_size = sizeof(struct dv1394_data),
232  .read_header = dv1394_read_header,
233  .read_packet = dv1394_read_packet,
234  .read_close = dv1394_close,
235  .flags = AVFMT_NOFILE,
236  .priv_class = &dv1394_class,
237 };
int format
Definition: dv1394.c:40
static const AVClass dv1394_class
Definition: dv1394.c:221
AVOption.
Definition: opt.h:251
av_default_item_name
#define DV1394_RING_FRAMES
Definition: dv1394.h:33
unsigned int n_clear_frames
Definition: dv1394.h:342
#define DV1394_PAL_FRAME_SIZE
Definition: dv1394.h:210
av_dlog(ac->avr,"%d samples - audio_convert: %s to %s (%s)\n", len, av_get_sample_fmt_name(ac->in_fmt), av_get_sample_fmt_name(ac->out_fmt), use_generic?ac->func_descr_generic:ac->func_descr)
static int dv1394_read_header(AVFormatContext *context)
Definition: dv1394.c:82
unsigned int channel
Definition: dv1394.h:272
Format I/O context.
Definition: avformat.h:944
static int dv1394_read_packet(AVFormatContext *context, AVPacket *pkt)
Definition: dv1394.c:119
static const AVOption options[]
Definition: dv1394.c:213
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:55
uint8_t
unsigned int n_frames
Definition: dv1394.h:276
AVOptions.
static AVPacket pkt
Definition: demuxing.c:56
enum pal_or_ntsc format
Definition: dv1394.h:279
DVDemuxContext * avpriv_dv_init_demux(AVFormatContext *s)
#define DV1394_NTSC_FRAME_SIZE
Definition: dv1394.h:209
unsigned int dropped_frames
Definition: dv1394.h:347
int index
Definition: dv1394.c:43
DVDemuxContext * dv_demux
Definition: dv1394.c:47
Main libavdevice API header.
void av_free(void *ptr)
Free a memory block which has been allocated with av_malloc(z)() or av_realloc(). ...
Definition: mem.c:183
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
int fd
Definition: dv1394.c:38
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:246
unsigned int api_version
Definition: dv1394.h:269
int size
char filename[1024]
input or output filename
Definition: avformat.h:994
int avail
Definition: dv1394.c:44
LIBAVUTIL_VERSION_INT
Definition: eval.c:55
unsigned int first_clear_frame
Definition: dv1394.h:338
NULL
Definition: eval.c:55
uint8_t * ring
Definition: dv1394.c:42
int avpriv_dv_produce_packet(DVDemuxContext *c, AVPacket *pkt, uint8_t *buf, int buf_size, int64_t pos)
int channel
Definition: dv1394.c:39
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:375
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:148
AVInputFormat ff_dv1394_demuxer
Definition: dv1394.c:228
static int dv1394_start(struct dv1394_data *dv)
Definition: dv1394.c:72
Describe the class of an AVClass context structure.
Definition: log.h:50
#define AV_OPT_FLAG_DECODING_PARAM
a generic parameter which can be set by the user for demuxing or decoding
Definition: opt.h:282
#define DV1394_API_VERSION
Definition: dv1394.h:41
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFilterBuffer structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Buffer references ownership and permissions
int active_frame
Definition: dv1394.h:334
int done
Definition: dv1394.c:45
static int dv1394_close(AVFormatContext *context)
Definition: dv1394.c:195
#define AVFMT_NOFILE
Demuxer will use avio_open, no opened file should be provided by the caller.
Definition: avformat.h:345
static int dv1394_reset(struct dv1394_data *dv)
Definition: dv1394.c:56
int avpriv_dv_get_packet(DVDemuxContext *c, AVPacket *pkt)
void * priv_data
Format private data.
Definition: avformat.h:964
#define DV1394_DEFAULT_CHANNEL
Definition: dv1394.h:31
const char * name
A comma separated list of short names for the format.
Definition: avformat.h:461
This structure stores compressed data.