Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

* [x] I looked for a similar issue and couldn't find any.
* [x] I tried with the latest version of GPAC. Installers available at http://gpac.io/downloads/gpac-nightly-builds/
* [x] I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). 

Hi,
The resolution of my video is 3840x1920.
I divided the video frame by the tile size 128x128 pixels to created a hevc-tiled MP4.
If I play the video by the command MP4Client 5000bps.hvc
it will stuck on black screen and shows  
![image](https://user-images.githubusercontent.com/18127960/120848395-5323d680-c5a7-11eb-9a7e-a1cd1c46eb40.png)


If I want to create dash contents, it also can not work. 
I need the small tile size for my research, it is very important for me.
Please help me.
Thank you guys.

The following are my commands for creating the mp4 and MPD.
 
.\kvazaar.exe  -i 4K.yuv --input-res 3840x1920 -o 5000bps.hvc --tiles 30x15 --slices tiles  -q 40 --mv-constraint frametilemargin  --bitrate 5000 --period 30 --input-fps 30 

Mp4box.exe -add 5000bps.hvc:split_tiles -new 5000bps.mp4
MP4Box -dash 1000 -rap -frag-rap -profile live -out dash_tiled.mpd 5000bps.mp4

Failed to playback 30x15 hevc-tiled MP4 and can not create dash contents
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Failed to playback 30x15 hevc-tiled MP4 and can not create dash contents
Issue date:

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Thanks for reporting your issue. Please make sure these boxes are checked before submitting your issue - thank you!

* [x] I looked for a similar issue and couldn't find any.
* [x] I tried with the latest version of GPAC. Installers available at http://gpac.io/downloads/gpac-nightly-builds/
* [x] I give enough information for contributors to reproduce my issue (meaningful title, github labels, platform and compiler, command-line ...). 

Hi,
The resolution of my video is 3840x1920.
I divided the video frame by the tile size 128x128 pixels to created a hevc-tiled MP4.
If I play the video by the command MP4Client 5000bps.hvc
it will stuck on black screen and shows  
![image](https://user-images.githubusercontent.com/18127960/120848395-5323d680-c5a7-11eb-9a7e-a1cd1c46eb40.png)


If I want to create dash contents, it also can not work. 
I need the small tile size for my research, it is very important for me.
Please help me.
Thank you guys.

The following are my commands for creating the mp4 and MPD.
 
.\kvazaar.exe  -i 4K.yuv --input-res 3840x1920 -o 5000bps.hvc --tiles 30x15 --slices tiles  -q 40 --mv-constraint frametilemargin  --bitrate 5000 --period 30 --input-fps 30 

Mp4box.exe -add 5000bps.hvc:split_tiles -new 5000bps.mp4
MP4Box -dash 1000 -rap -frag-rap -profile live -out dash_tiled.mpd 5000bps.mp4

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