what is the difference between "quarter" and "full" resolution multi pass mode in obs?

[ILIG GAMER]

1. In what scenario should I use " Full " and in which should I use the " Quarter Resolution " ? ( if for example, I have an Ultimate system, should I use Full Res? )

2. Should I use " Full " for streaming to get better quality ? or it's just going to give delay between the video is ready and is sent to the streaming service? or both the quality and delay ?

3. As for recording with CQP, does it matter if I use " full " instead or Quarter ?

4. And overall, does the " Full Resolution " put more pressure on my system ?

 

[koala]

This is a setting that changes Nvenc encoder behavior. It's an encoder optimization available from the more recent RTX Nvidia GPUs. Since this encoder is a dedicated circuit within the GPU, changing this setting will just change resource demands within the encoder but not the 3D resources used by games or apps.

As far as I understand, this setting is about gathering frame statistics in the 1st path of the multipass encoder mode. These statistics help with better compression of the data. By only gathering 1/4 of the image data, the statistics are slightly worse than with full resolution, but needs less resources within the encoder, so it is able to encode higher resolutions or higher fps. This becomes important if the encoder is just not able to achieve the desired fps (for example 60) by a small amount. The negative result of quarter resolution is slightly bigger file size, which is negligible for any non-bitrate orientated rate control such as CQP. The file will be the same quality but just a few kilobytes bigger. With CBR and streaming, bigger data size means tiny quality loss, because the quality has to be reduced to achieve the same bitrate. However, this is probably not perceptible, while frame drops due to encoder overload are very perceptible.

 

[ILIG GAMER]

This is a setting that changes Nvenc encoder behavior. It's an encoder optimization available from the more recent RTX Nvidia GPUs. Since this encoder is a dedicated circuit within the GPU, changing this setting will just change resource demands within the encoder but not the 3D resources used by games or apps.

As far as I understand, this setting is about gathering frame statistics in the 1st path of the multipass encoder mode. These statistics help with better compression of the data. By only gathering 1/4 of the image data, the statistics are slightly worse than with full resolution, but needs less resources within the encoder, so it is able to encode higher resolutions or higher fps. This becomes important if the encoder is just not able to achieve the desired fps (for example 60) by a small amount. The negative result of quarter resolution is slightly bigger file size, which is negligible for any non-bitrate orientated rate control such as CQP. The file will be the same quality but just a few kilobytes bigger. With CBR and streaming, bigger data size means tiny quality loss, because the quality has to be reduced to achieve the same bitrate. However, this is probably not perceptible, while frame drops due to encoder overload are very perceptible.

Thanks a lot Koala! That was comprehensive!

So, basically, 1/4 is more efficient!

Just for my own knowledge; by statistics, you mean data, right?