From d6b6d7aef458e1c1ce6997929d38aaa48fe637c2 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sat, 8 May 2010 08:55:42 -0300 Subject: [PATCH] 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 Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/gspca/ov519.c | 21 ++++++++++++++++++--- 1 file changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/media/video/gspca/ov519.c b/drivers/media/video/gspca/ov519.c index f36e11a0458..aa3de2f5a27 100644 --- a/drivers/media/video/gspca/ov519.c +++ b/drivers/media/video/gspca/ov519.c @@ -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, -- 2.41.0