V4L/DVB: gspca_ovfx2: drop first frames in stream if not synced

With the ovfx2 bridge sometimes the first few frames in a stream
would be no good, as the bridge and sensor are not in complete hsync /
vsync yet. This can easily be detected by checking the framesize. So if the
framesize is short and it is one of the 1ste 3 frames after an sd_start,
drop it.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans de Goede 2010-05-08 08:55:42 -03:00 committed by Mauro Carvalho Chehab
parent ccfb302882
commit d6b6d7aef4

View File

@ -90,6 +90,7 @@ struct sd {
#define QUALITY_DEF 50
__u8 stopped; /* Streaming is temporarily paused */
__u8 first_frame;
__u8 frame_rate; /* current Framerate */
__u8 clockdiv; /* clockdiv override */
@ -3961,6 +3962,8 @@ static int sd_start(struct gspca_dev *gspca_dev)
sd_reset_snapshot(gspca_dev);
sd->snapshot_pressed = 0;
sd->first_frame = 3;
ret = ov51x_restart(sd);
if (ret < 0)
goto out;
@ -4153,13 +4156,25 @@ static void ovfx2_pkt_scan(struct gspca_dev *gspca_dev,
u8 *data, /* isoc packet */
int len) /* iso packet length */
{
struct sd *sd = (struct sd *) gspca_dev;
struct gspca_frame *frame;
gspca_frame_add(gspca_dev, INTER_PACKET, data, len);
/* A short read signals EOF */
if (len < OVFX2_BULK_SIZE) {
gspca_frame_add(gspca_dev, LAST_PACKET, data, len);
/* If the frame is short, and it is one of the first ones
the sensor and bridge are still syncing, so drop it. */
if (sd->first_frame) {
sd->first_frame--;
frame = gspca_get_i_frame(gspca_dev);
if (!frame || (frame->data_end - frame->data) <
(sd->gspca_dev.width * sd->gspca_dev.height))
gspca_dev->last_packet_type = DISCARD_PACKET;
}
gspca_frame_add(gspca_dev, LAST_PACKET, NULL, 0);
gspca_frame_add(gspca_dev, FIRST_PACKET, NULL, 0);
return;
}
gspca_frame_add(gspca_dev, INTER_PACKET, data, len);
}
static void sd_pkt_scan(struct gspca_dev *gspca_dev,