WHIP Ingress with Simulcast (bypass transcoding) #352
Description
There is a project to bring Simulcast publishing to OBS Whip by Sean-Der - obsproject/obs-studio#10885
Currently it works with his Glimesh/broadcast-box and OvenMediaEngine (both opensource projects). You may ask why use Ingress when livekit can ingest Simulcast with a web browser. Well, OBS can produce much higher bitrates and encode video at higher quality compared to a web browser and some people simply prefer OBS over Web based publishing.
When I try simulcast publishing with 3 layers, to an ingress that has bypass transcoding, it can see the tracks but track switching is unavailable.
lk room participants get --room whip whip
Using url, api-key, api-secret from environment
Using url, api-key, api-secret from environment
{
"sid": "PA_uwLQg9Esga8z",
"identity": "whip",
"state": 2,
"tracks": [
{
"sid": "TR_AMB6CHz2snxRrZ",
"source": 2,
"mime_type": "audio/opus",
"mid": "1",
"stereo": true,
"stream": "camera",
"version": {
"unix_micro": 1747025474889633
},
"audio_features": [
0
]
},
{
"sid": "TR_VCzNxnGMMBe75H",
"type": 1,
"width": 1920,
"height": 1080,
"simulcast": true,
"source": 1,
"layers": [
{
"quality": 2,
"width": 640,
"height": 360,
"ssrc": 3072329210
},
{
"quality": 1,
"width": 1280,
"height": 720,
"ssrc": 745007582
},
{
"width": 1920,
"height": 1080,
"ssrc": 421479776
}
],
"mime_type": "video/H264",
"mid": "2",
"codecs": [
{
"mime_type": "video/H264",
"mid": "2",
"cid": "IN_qEUWGi5Mp8XM",
"layers": [
{
"quality": 2,
"width": 640,
"height": 360,
"ssrc": 3072329210
},
{
"quality": 1,
"width": 1280,
"height": 720,
"ssrc": 745007582
},
{
"width": 1920,
"height": 1080,
"ssrc": 421479776
}
]
}
],
"stream": "camera",
"version": {
"unix_micro": 1747025475059295
}
}
],
"joined_at": 1747025474,
"joined_at_ms": 1747025474813,
"name": "whip",
"version": 7,
"permission": {
"can_publish": true,
"can_publish_data": true,
"can_update_metadata": true
},
"region": "de-berlin",
"is_publisher": true,
"kind": 1,
"attributes": {
"ingress.ingressID": "IN_qEUWGi5Mp8XM",
"ingress.resourceID": "WH_yWf8R4Amr8Nz"
}
}
When I try it to an ingress that has WHIP with transcoding enabled, it refuses it, which is okay.
2025-05-12T06:27:58.868+0200 INFO ingress service/service.go:316 received ingress info {"nodeID": "NE_t5RhELR7WZep", "ingressID": "IN_tF4cW97aR59n", "streamKey": "h3vxyWasTHCC", "resourceID": "WH_qKmDeLfC3pT6", "ingressInfo": "ingress_id:\"IN_tF4cW97aR59n\" name:\"whiptranscoding\" stream_key:\"{h3v...HCC}\" url:\"http://xx.xxx.com:8038/whip\" input_type:WHIP_INPUT enable_transcoding:true audio:{source:MICROPHONE preset:OPUS_STEREO_96KBPS} video:{source:CAMERA preset:H264_1080P_30FPS_3_LAYERS} room_name:\"whiptranscoding\" participant_identity:\"whiptranscoding\" participant_name:\"whiptranscoding\" reusable:true state:{status:ENDPOINT_BUFFERING started_at:1747024078864848760 updated_at:1747024078865295343 resource_id:\"WH_qKmDeLfC3pT6\"}"}
2025-05-12T06:27:58.868+0200 WARN ingress service/service.go:174 ingress failed {"nodeID": "NE_t5RhELR7WZep", "error": "simulcast is not supported when transcoding"}
Considering you allow Simulcast on WHIP bypass transcoding, is there any plan to get it working?
PS: high, medium, low mapping in simulcast (whip - bypass) is in reverse order.