# Inputs · NDI · OMT · SRT · RTMP · SDI · Capture: Quality, latency & ports

> What each input costs, and what to open in a firewall.

Glider documentation · Playout & On Air · Web page: https://cgglider.com/docs/inputs/quality/

Sections of this page: [How inputs work](https://cgglider.com/docs/inputs.md) · [Quality, latency & ports](https://cgglider.com/docs/inputs/quality.md) · [Screen & app capture](https://cgglider.com/docs/inputs/capture.md)

| Setting | Meaning |
| --- | --- |
| Preview quality | JPEG quality of the pictures Feeds receive: High, Medium or Low. Lower costs less bandwidth to browsers on other machines. |
| Picture size | Scale the input down to at most 2160p, 1080p, 720p or 540p before it is sent, or keep the source size. |
| Picture port | The WebSocket port pictures are served on. 0 picks a free port each start; set a fixed one to open it in a firewall when /view runs on another machine. |

Encoding adds about one frame; the source's own transport (NDI, SRT latency, an RTMP encoder's buffer) comes on top. Audio from inputs is not carried.

> **ffmpeg is required:** Every input is encoded for Feeds with ffmpeg — the same one Settings › Outputs uses. Settings › Inputs says which protocols this ffmpeg can read.