Can't play rtsp stream without sound

[lukegluke]

Took an example from https://github.com/wang-bin/mdk-examples/issues/9 and changed a player source to "rtsp://192.168.1.57:8080/h264_ulaw.sdp" to connect to virtual local ip camera - the android smartphone with running IP Webcam app. It works if sound is turned on in IP Webcam app, but not shown anything if video is streamed without sound. Vlc plays in both cases.

Windows 10 Qt 5.9.5, MinGW 5.3.0 32bit MDK 0.11.0 (git 6dd01c9)

[wang-bin]

I have no such rtsp stream. but a local video file without audio works for me.

[lukegluke]

I forgot to paste link to IP Webcam app: https://play.google.com/store/apps/details?id=com.pas.webcam Maybe you have opportunity to test with it using Android phone.

[wang-bin]

can you send me an apk? I'm unable to install apps from google play in my country

[lukegluke]

Ok, I've download it from https://apkpure.com/ip-webcam/com.pas.webcam

IP Webcam_v1.14.37.759 (aarch64)_apkpure.com.zip

[wang-bin]

Can you try glfwplay example in the sdk? I'm failed to open the rtsp stream using mdk, ffplay and vlc.

[lukegluke]

Sorry, I don't have tools to build it. On my side I'm able to play rtcp stream from IP Webcam apk using vlc.

[wang-bin]

glfwplay is a prebuilt binary in mdk-sdk/bin

[lukegluke]

Ah, ok. I got the same result: it works only if sound is turned on in IP Webcam app, otherwise nothing - black screen.

[wang-bin]

Finally I can play the rtsp stream generated by this app. Here is the MediaInfo printed by mdk

Format: rtsp, range: 99 +0ms, bitrate: 0, size: 0
Metadata:
  title: IP Webcam
Streams: 2
 Audio:
  stream#1, range: -209146758205323714 +0ms, frames: 0
  codec: pcm_s16be tag: 0 profile: -99 level: -99, sample size: 0/16, s16 mono(1) @44100Hz, bitrate: 705600
 Video:
  stream#0, range: 99 +0ms, frames: 0
  codec: h264 tag: 0 profile: 578 level: 40, sample size: 8/0, yuv420p, bpc:8, bpp:12(8,8,8), bitrate: 0, 1920x1080, fps: 90000, bframes: 0
D 2021-04-22 22:19:59.201@0x16c233000:   extra data(28): 00 00 00 01 67 42 C0 28 8C 8D 40 3C 01 12 F2 C0 3C 22 11 A8 00 00 00 01 68 CE 3C 80 

The stream contains an invalid audio track, so video can not sync to audio. You can call player.setActiveTracks(MediaType::Audio, {}) to disable audio track, then video displays correctly.

[wang-bin]

fixed in the latest build