#endif
#include <linux/videodev2.h>
#endif
-#include <time.h>
#include "libavutil/imgutils.h"
#include "libavutil/log.h"
#include "libavutil/opt.h"
#include "avdevice.h"
+#include "timefilter.h"
#include "libavutil/parseutils.h"
#include "libavutil/pixdesc.h"
#include "libavutil/avstring.h"
#define V4L_RAWFORMATS 1
#define V4L_COMPFORMATS 2
+/**
+ * Return timestamps to the user exactly as returned by the kernel
+ */
+#define V4L_TS_DEFAULT 0
+/**
+ * Autodetect the kind of timestamps returned by the kernel and convert to
+ * absolute (wall clock) timestamps.
+ */
+#define V4L_TS_ABS 1
+/**
+ * Assume kernel timestamps are from the monotonic clock and convert to
+ * absolute timestamps.
+ */
+#define V4L_TS_MONO2ABS 2
+
+/**
+ * Once the kind of timestamps returned by the kernel have been detected,
+ * the value of the timefilter (NULL or not) determines whether a conversion
+ * takes place.
+ */
+#define V4L_TS_CONVERT_READY V4L_TS_DEFAULT
+
struct video_data {
AVClass *class;
int fd;
int frame_size;
int interlaced;
int top_field_first;
+ int ts_mode;
+ TimeFilter *timefilter;
+ int64_t last_time_m;
int buffers;
void **buf_start;
unsigned int *buf_len;
char *standard;
int channel;
- char *video_size; /**< String describing video size,
- set by a private option. */
char *pixel_format; /**< Set by a private option. */
int list_format; /**< Set by a private option. */
char *framerate; /**< Set by a private option. */
pkt->size = 0;
}
+#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
+static int64_t av_gettime_monotonic(void)
+{
+ struct timespec tv;
+
+ clock_gettime(CLOCK_MONOTONIC, &tv);
+ return (int64_t)tv.tv_sec * 1000000 + tv.tv_nsec / 1000;
+}
+#endif
+
+static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts)
+{
+ struct video_data *s = ctx->priv_data;
+ int64_t now;
+
+ now = av_gettime();
+ if (s->ts_mode == V4L_TS_ABS &&
+ ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) {
+ av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n");
+ s->ts_mode = V4L_TS_CONVERT_READY;
+ return 0;
+ }
+#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
+ now = av_gettime_monotonic();
+ if (s->ts_mode == V4L_TS_MONO2ABS ||
+ (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) {
+ int64_t period = av_rescale_q(1, ctx->streams[0]->codec->time_base,
+ AV_TIME_BASE_Q);
+ av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n");
+ /* microseconds instead of seconds, MHz instead of Hz */
+ s->timefilter = ff_timefilter_new(1, period, 1.0E-6);
+ s->ts_mode = V4L_TS_CONVERT_READY;
+ return 0;
+ }
+#endif
+ av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n");
+ return AVERROR(EIO);
+}
+
+static int convert_timestamp(AVFormatContext *ctx, int64_t *ts)
+{
+ struct video_data *s = ctx->priv_data;
+
+ if (s->ts_mode) {
+ int r = init_convert_timestamp(ctx, *ts);
+ if (r < 0)
+ return r;
+ }
+#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC)
+ if (s->timefilter) {
+ int64_t nowa = av_gettime();
+ int64_t nowm = av_gettime_monotonic();
+ ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m);
+ s->last_time_m = nowm;
+ *ts = ff_timefilter_eval(s->timefilter, *ts - nowm);
+ }
+#endif
+ return 0;
+}
+
static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
{
struct video_data *s = ctx->priv_data;
pkt->data= s->buf_start[buf.index];
pkt->size = buf.bytesused;
pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
+ res = convert_timestamp(ctx, &pkt->pts);
+ if (res < 0)
+ return res;
pkt->destruct = mmap_release_buffer;
buf_descriptor = av_malloc(sizeof(struct buff_data));
if (buf_descriptor == NULL) {
avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
- if (s->video_size &&
- (res = av_parse_video_size(&s->width, &s->height, s->video_size)) < 0) {
- av_log(s1, AV_LOG_ERROR, "Could not parse video size '%s'.\n",
- s->video_size);
- goto out;
- }
-
if (s->pixel_format) {
AVCodec *codec = avcodec_find_decoder_by_name(s->pixel_format);
static const AVOption options[] = {
{ "standard", "TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC },
{ "channel", "TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, INT_MAX, DEC },
- { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(video_size), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
+ { "video_size", "A string describing frame size, such as 640x480 or hd720.", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC },
{ "pixel_format", "Preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
{ "input_format", "Preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
{ "framerate", "", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC },
{ "all", "Show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" },
{ "raw", "Show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" },
{ "compressed", "Show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.dbl = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" },
+ { "timestamps", "Kind of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, 2, DEC, "timestamps" },
+ { "default", "Use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.dbl = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" },
+ { "abs", "Use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.dbl = V4L_TS_ABS }, 0, 2, DEC, "timestamps" },
+ { "mono2abs", "Force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.dbl = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" },
+ { "ts", "Kind of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.dbl = 0 }, 0, 2, DEC, "timestamps" },
{ NULL },
};
projects / ffmpeg / blobdiff