Improving Quality with FFmpeg NVENC

When it comes to live streaming, maintaining high-quality video without sacrificing bitrate can be a challenge. In this article, we'll explore ways to improve the quality of your output using FFmpeg and NVENC.

First, let's take a look at the current command:

```

-c:v h264_nvenc -cbr true -b:v 9M -preset slow -c:a copy -gpu 1 -f flv 'rtmp://youtube_server/streamkey'

-c:v h264_nvenc -cbr true -b:v 6M -preset slow -c:a copy -gpu 1 -f flv 'rtmp://facebook_server/streamkey'

-c:v h264_nvenc -cbr true -b:v 6M -preset slow -c:a copy -gpu 1 -f flv 'rtmp://twitch_server/streamkey'

ffmpeg -hide_banner -i rtmp://localhost:1935/live/stream

```

This command uses NVENC to encode the video and copy the audio. However, when there's action on the stream (such as in-game movements), the quality of the output drops, resulting in artifacts.

One way to improve the quality without increasing the bitrate is to experiment with different presets and profiles. For example, you can try using a higher preset like `medium` or `high` instead of `slow`. This may help maintain better quality at the cost of increased CPU usage.

Another approach is to use NVENC's advanced features, such as deblocking filters and chroma subsampling. These settings can be adjusted using options like `-deblock` and `-chromaloc`. For example:

```

-c:v h264_nvenc -deblock 1:0:2 -chromaloc 1 -cbr true -b:v 9M -preset slow ...

```

This may help reduce the occurrence of artifacts and improve overall quality.

Regarding the code itself, using `tee` can be an effective way to split the output into multiple streams while maintaining high quality. `Tee` allows you to duplicate the input stream and send it to multiple outputs, which can be useful for streaming to multiple platforms simultaneously.

Here's an example of how you could use `tee` in your command:

```

ffmpeg -hide_banner -i rtmp://localhost:1935/live/stream \

-c:v h264_nvenc -deblock 1:0:2 -chromaloc 1 -cbr true -b:v 9M -preset slow \

-f flv -tee 'out1'; 'out1' \

'rtmp://youtube_server/streamkey' \

-f flv -tee 'out2'; 'out2' \

'rtmp://facebook_server/streamkey' \

-f flv -tee 'out3'; 'out3' \

'rtmp://twitch_server/streamkey'

```

In this example, the input stream is duplicated using `tee`, and each output is sent to a different platform.

By experimenting with different presets, profiles, and options like deblocking filters and chroma subsampling, you can improve the quality of your output without increasing the bitrate. Additionally, using `tee` can help simplify your streaming setup while maintaining high-quality video for multiple platforms.

Ffmpeg nvenc