A BUNCH of HLS (and related) progress

- Add support for fMP4 segments
- Add initInput (supported by ISOBMFF and MPEG-TS)
- Input.isSupported()
- Refactored file size retrieval logic, the file size can now be retrieved alongside the first read.
- Add support for unsized UrlSources
- Add support for multiple trun boxes in a row for the same track (as the spec literally says lol)
- Add support for more M3U8 features
- Fix faulty line reader
- MPEG-TS improvements: support video parameters not in first packet, support better key frame detection, support extension PES packets without PTS
- Fix reorder buffer being 1 element too small

src/input-format.ts

@@ -66,7 +66,11 @@ export abstract class IsobmffInputFormat extends InputFormat {
 		slice.skip(4);
 		const fourCc = readAscii(slice, 4);
 
-		if (fourCc !== 'ftyp') {
+		if (
+			fourCc !== 'ftyp'
+			&& fourCc !== 'styp' // Segment
+			&& fourCc !== 'moof' // Not a legal segment, but seen in practice (sigh)
+		) {
 			return null;
 		}