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| Warning |
|---|
When using HLS ABR on a single server, any published stream will be transcoded to a number of qualities. This requires a lot of server CPU cores and RAM. |
Transcoding to higher resolutions prevention
Since build 5.2.1611, if a stream published has a less picture height than some profiles listed in hls_abr_profiles.yml, then all the variants with higher resolutions will not be encoded and will not be included to manfest. For example, the manifest will look as follows when original stream has 960x540 resolution:
| Code Block | ||
|---|---|---|
| ||
#EXTM3U
#EXT-X-STREAM-INF:BANDWIDTH=300000,RESOLUTION=320x180,CODECS="avc1.42e01f,mp4a.40.2"
180/180.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=500000,RESOLUTION=428x240,CODECS="avc1.42e01f,mp4a.40.2"
240/240.m3u8
#EXT-X-STREAM-INF:BANDWIDTH=1000000,RESOLUTION=848x480,CODECS="avc1.42e01f,mp4a.40.2"
480/480.m3u8 |
because there will not be upscale to 1280x720.
If the stream resolution is lower than a minimal profile, this stream will be transcoded to the minimal available profile, and the only variant will be included to manifest
| Code Block | ||
|---|---|---|
| ||
#EXTM3U
#EXT-X-STREAM-INF:BANDWIDTH=300000,RESOLUTION=320x180,CODECS="avc1.42e01f,mp4a.40.2"
180/180.m3u8 |
If there is a profile without both width and height parameters, the stream will be transcoded to its original resolution with GOP and FPS defined in the profile, and this variant will always be included to manifest:
| Code Block | ||
|---|---|---|
| ||
profiles:
original:
video:
codec : h264
codecImpl : OPENH264
gop : 60
fps : 30 |
Qualities order in HLS ABR manifest
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