From 80fa4f07fd6d33500b26275a5405d5b49cf2ff6a Mon Sep 17 00:00:00 2001
From: =?utf8?q?Nikola=20Forr=C3=B3?= <nikola.forro@gmail.com>
Date: Sun, 20 Dec 2015 09:57:17 -0200
Subject: [PATCH] [media] usbtv: discard redundant video fields
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There are many dropped fields with some sources, leading to many
redundant fields without counterparts. When this redundant field
is odd, a new frame is pushed containing this odd field interleaved
with whatever was left in the buffer, causing video artifacts.
Do not push a new frame after processing every odd field, but do it
only after those which come after an even field.
Signed-off-by: Nikola Forró <nikola.forro@gmail.com>
Acked-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
---
drivers/media/usb/usbtv/usbtv-video.c | 33 +++++++++++++++------------
drivers/media/usb/usbtv/usbtv.h | 1 +
2 files changed, 20 insertions(+), 14 deletions(-)
diff --git a/drivers/media/usb/usbtv/usbtv-video.c b/drivers/media/usb/usbtv/usbtv-video.c
index 4ebb33943f9a0..4ecb27b2d619a 100644
--- a/drivers/media/usb/usbtv/usbtv-video.c
+++ b/drivers/media/usb/usbtv/usbtv-video.c
@@ -312,20 +312,24 @@ static void usbtv_image_chunk(struct usbtv *usbtv, __be32 *chunk)
usbtv_chunk_to_vbuf(frame, &chunk[1], chunk_no, odd);
usbtv->chunks_done++;
- /* Last chunk in a frame, signalling an end */
- if (odd && chunk_no == usbtv->n_chunks-1) {
- int size = vb2_plane_size(&buf->vb.vb2_buf, 0);
- enum vb2_buffer_state state = usbtv->chunks_done ==
- usbtv->n_chunks ?
- VB2_BUF_STATE_DONE :
- VB2_BUF_STATE_ERROR;
-
- buf->vb.field = V4L2_FIELD_INTERLACED;
- buf->vb.sequence = usbtv->sequence++;
- buf->vb.vb2_buf.timestamp = ktime_get_ns();
- vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
- vb2_buffer_done(&buf->vb.vb2_buf, state);
- list_del(&buf->list);
+ /* Last chunk in a field */
+ if (chunk_no == usbtv->n_chunks-1) {
+ /* Last chunk in a frame, signalling an end */
+ if (odd && !usbtv->last_odd) {
+ int size = vb2_plane_size(&buf->vb.vb2_buf, 0);
+ enum vb2_buffer_state state = usbtv->chunks_done ==
+ usbtv->n_chunks ?
+ VB2_BUF_STATE_DONE :
+ VB2_BUF_STATE_ERROR;
+
+ buf->vb.field = V4L2_FIELD_INTERLACED;
+ buf->vb.sequence = usbtv->sequence++;
+ buf->vb.vb2_buf.timestamp = ktime_get_ns();
+ vb2_set_plane_payload(&buf->vb.vb2_buf, 0, size);
+ vb2_buffer_done(&buf->vb.vb2_buf, state);
+ list_del(&buf->list);
+ }
+ usbtv->last_odd = odd;
}
spin_unlock_irqrestore(&usbtv->buflock, flags);
@@ -639,6 +643,7 @@ static int usbtv_start_streaming(struct vb2_queue *vq, unsigned int count)
if (usbtv->udev == NULL)
return -ENODEV;
+ usbtv->last_odd = 1;
usbtv->sequence = 0;
return usbtv_start(usbtv);
}
diff --git a/drivers/media/usb/usbtv/usbtv.h b/drivers/media/usb/usbtv/usbtv.h
index 19cb8bf7c4e9b..161b38d5cfa04 100644
--- a/drivers/media/usb/usbtv/usbtv.h
+++ b/drivers/media/usb/usbtv/usbtv.h
@@ -95,6 +95,7 @@ struct usbtv {
int width, height;
int n_chunks;
int iso_size;
+ int last_odd;
unsigned int sequence;
struct urb *isoc_urbs[USBTV_ISOC_TRANSFERS];
--
2.30.2