SPS parse failure

[koush]

Here's the sprop-parameter-sets:

a=fmtp:96 packetization-mode=1;profile-level-id=4D0029;sprop-parameter-sets=J00AKedAPAET8s1AQEB8AAADAAQAAAMAoNGADqYAFfl//wKA,KO48gA==

const sps = Buffer.from('J00AKedAPAET8s1AQEB8AAADAAQAAAMAoNGADqYAFfl//wKA', 'base64');
const pps = Buffer.from('KO48gA==', 'base64');

This may be invalid data? But it is what Wyze cameras are returning in their SDP (and throwing during parse).

/Volumes/Dev/scrypted/plugins/prebuffer-mixin/node_modules/h264-sps-parser/dist/bitstream.js:17
            byt = view.getUint8(byteoffset);
                       ^

Uncaught RangeError: Offset is outside the bounds of the DataView
    at DataView.getUint8 (<anonymous>)
    at ExpGolomInit (/Volumes/Dev/scrypted/plugins/prebuffer-mixin/node_modules/h264-sps-parser/dist/bitstream.js:17:24)
    at Bitstream.ExpGolomb (/Volumes/Dev/scrypted/plugins/prebuffer-mixin/node_modules/h264-sps-parser/dist/bitstream.js:30:49)
    at hrd_parameters (/Volumes/Dev/scrypted/plugins/prebuffer-mixin/node_modules/h264-sps-parser/dist/vui.js:9:40)
    at Object.getVUIParams (/Volumes/Dev/scrypted/plugins/prebuffer-mixin/node_modules/h264-sps-parser/dist/vui.js:105:9)
    at Object.parse (/Volumes/Dev/scrypted/plugins/prebuffer-mixin/node_modules/h264-sps-parser/dist/index.js:111:34)
    at /Volumes/Dev/scrypted/plugins/prebuffer-mixin/<repl>.ts:1:4
    at Script.runInThisContext (node:vm:129:12)
    at runInContext (/Users/koush/.nvm/versions/node/v18.14.2/lib/node_modules/ts-node/src/repl.ts:673:19)
    at Object.execCommand (/Users/koush/.nvm/versions/node/v18.14.2/lib/node_modules/ts-node/src/repl.ts:639:28)

[ak-s]

NAL units must be stripped of emulation prevention bytes (0x03) before parsing (see ITU-T Rec. H.264).
0x00000300 -> 0x000000
0x00000301 -> 0x000001
0x00000302 -> 0x000002
0x00000303 -> 0x000003

Buffer.from('J00AKedAPAET8s1AQEB8AAADAAQAAAMAoNGADqYAFfl//wKA', 'base64');

It has 2 of them.

[gliese1337]

Kind of odd that I never came across this problem myself. nalparser now exports a helper function to remove emulation prevention bytes from a buffer before parsing. I'll have to publish an updated version to NPM before closing this.