[FFmpeg-devel] [PATCH] avdevice/decklink_dec: fix no warning message if no input signal detected

[Marton Balint]

On Fri, 19 Jun 2020, Limin Wang wrote:

> On Thu, Jun 18, 2020 at 07:37:50PM +0200, Marton Balint wrote:
>> 
>> 
>> On Thu, 18 Jun 2020, lance.lmwang at gmail.com wrote:
>> 
>> >From: Limin Wang <lance.lmwang at gmail.com>
>> >
>> >Signed-off-by: Limin Wang <lance.lmwang at gmail.com>
>> >---
>> >libavdevice/decklink_dec.cpp | 2 +-
>> >1 file changed, 1 insertion(+), 1 deletion(-)
>> >
>> >diff --git a/libavdevice/decklink_dec.cpp b/libavdevice/decklink_dec.cpp
>> >index 82106aa..90569dc 100644
>> >--- a/libavdevice/decklink_dec.cpp
>> >+++ b/libavdevice/decklink_dec.cpp
>> >@@ -751,7 +751,7 @@ HRESULT decklink_input_callback::VideoInputFrameArrived(
>> >                }
>> >            }
>> >
>> >-            if (!no_video) {
>> >+            if (no_video) {
>> >                av_log(avctx, AV_LOG_WARNING, "Frame received (#%lu) - No input signal detected "
>> >                        "- Frames dropped %u\n", ctx->frameCount, ++ctx->dropped);
>> >            }
>> 
>> No, this is good as is, the !no_video condition ensures that it is
>> only logged once when the input actually disappears, and not for
>> every consecutive frame with no input.
>
> It's good point, but if no input signal after run, no any warning message.

I don't understand what you are saying here.

> I don't think it's helpful to check the signal status,

What do you mean?

> also the dropped message 
> isn't correct then, as it'll not count for every dropped frame by the condition.

That is true, a patch which fixes the number of dropped frames only is 
welcome.

Thanks,
Marton