First concern - why are you using the raw REST API instead of one of the many supported client SDKs in various languages? I would encourage you to use the supported SDKs' instead of rolling your own client SDK code - it can cause a lot of issues with Retry policies and ARM resource management for long running operations. That's all built into the SDKs.
Can you work with Node.js or Typescript? https://github.com/Azure-Samples/media-services-v3-node-tutorials/blob/main/VideoEncoding/Encoding_H264_ContentAware_Constrained/index.ts
To answer your question - you are looking to use the JobIntputHttp object in the REST api (same name in the SDKs) - see here for the full Open API schema definition of that entity:
https://github.com/Azure/azure-rest-api-specs/blob/db38bff6ab588858ee1df6f86ae1d0ec4d2d5781/specification/mediaservices/resource-manager/Microsoft.Media/stable/2021-06-01/Encoding.json#L1932
"JobInputHttp": {
"x-ms-discriminator-value": "#Microsoft.Media.JobInputHttp",
"allOf": [
{
"$ref": "#/definitions/JobInputClip"
}
],
"properties": {
"baseUri": {
"type": "string",
"description": "Base URI for HTTPS job input. It will be concatenated with provided file names. If no base uri is given, then the provided file list is assumed to be fully qualified uris. Maximum length of 4000 characters. The query strings will not be returned in service responses to prevent sensitive data exposure."
}
},
"type": "object",
"description": "Represents HTTPS job input."
},