user11789: Can you help me to figure out what's going on here?
I'm trying to capture in realtime my screen and save it losslessy via ffv1 codec.

CPU usage while recording is not so much, as comparison h264 in ultrafast profile takes lot more cpu than ffv1.
Here's the command I'm using:
ffmpeg -f dshow -y -i video="screen-capture-recorder" -framerate 30 -c:v ffv1 -pix_fmt bgra -t 5 capture.mkv

I tried also adding the tuning and rtbufsize but nothing changes :\
ffmpeg -f dshow -y -i video="screen-capture-recorder" -framerate 30 -c:v ffv1 -pix_fmt bgra -t 5 -tune zerolatency -rtbufsize 2100M capture.mkv

Any suggestions? :)

user1871: I get the same result with your commands, however if I skip the pixel format conversion and use the input pixel format 'bgr0', then except for an initial frame drop, I get no further drops. Note that tune is a x264 parameter - it has no relevance for FFV1.
And if I use gdigrab (my preferred grabbing device), I get no frame drops at all, even with bgra:-
ffmpeg -y -f gdigrab -i desktop -framerate 30 -c:v ffv1 -pix_fmt bgra -t 5 capture.mkv


11789: <p>Can you help me to figure out what's going on here?</p>

<p>I'm trying to capture in realtime my screen and save it losslessy via ffv1 codec.</p>

<p><a href="https://i.stack.imgur.com/nzXQM.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/nzXQM.png" alt="ffmpeg encoding ffv1 errors on console"></a></p>

<p>CPU usage while recording is not so much, as comparison h264 in ultrafast profile takes lot more cpu than ffv1.</p>

<p>Here's the command I'm using:</p>

<pre><code>ffmpeg -f dshow -y -i video="screen-capture-recorder" -framerate 30 -c:v ffv1 -pix_fmt bgra -t 5 capture.mkv
</code></pre>

<p>I tried also adding the tuning and rtbufsize but nothing changes :\</p>

<pre><code>ffmpeg -f dshow -y -i video="screen-capture-recorder" -framerate 30 -c:v ffv1 -pix_fmt bgra -t 5 -tune zerolatency -rtbufsize 2100M capture.mkv
</code></pre>

<p>Any suggestions? :)</p>
 1871: <p>I get the same result with your commands, however if I skip the pixel format conversion and use the input pixel format 'bgr0', then except for an initial frame drop, I get no further drops. Note that tune is a x264 parameter - it has no relevance for FFV1.</p>

<p>And if I use gdigrab (my preferred grabbing device), I get no frame drops at all, even with bgra:-</p>

<pre><code>ffmpeg -y -f gdigrab -i desktop -framerate 30 -c:v ffv1 -pix_fmt bgra -t 5 capture.mkv
</code></pre>
