Resolution Format
res
The resolution of a video served with fm=mp4 can be controlled with the res parameter. The res parameter accepts the values of high, medium or low, though the available resolutions depend on the resolution of the uploaded video.
The res parameter will only alter the resolution of a video if fm=mp4 is used.
When res is not specified, the Video API will serve MP4’s at a resolution of up to 1080p - this is the maximum resolution for MP4 videos, and can also be returned by using the parameter value res=high. Note that this will only return 1080p if the uploaded video is at least 1080p and above.
A video requested with res=medium will be a step down in resolution from high, and a request for low will be a step down in resolution from medium.
In general, high corresponds to a FHD or HD video (up to 1080p), medium corresponds to a video that is SD, and low corresponds to a video with a resolution lower than medium.
Depending on the original resolution of an uploaded video, there may be up to 3 retrievable resolutions.
For example, if the origin video is 480p, only two resolutions may be retrievable: 480p (res=medium) and a resolution lower than 480p, i.e. res=low. In this scenario, if you request this video with res=high (ex: fm=mp4&res=high), you receive the highest resolution available (res=medium). As an example, here are some possible resolution levels for a 480p SD origin video:
https://{SUBDOMAIN}.imgix.video/480p-video?fm=mp4&res=high, returns the highest resolution video available (480p)https://{SUBDOMAIN}.imgix.video/480p-video?fm=mp4&res=medium, returns a SD video (480p)https://{SUBDOMAIN}.imgix.video/480p-video?fm=mp4&res=low, returns a video with a resolution lower thanres=medium(240p)
If the origin video’s resolution is lower than SD, there will be only one resolution available, res=low. In this case, high, medium, and low will all correspond to the same video resolution (the only one available).