GPUImage reads ITU_R_601_4 format video with no supportsFastTextureUpload resulted in teared image buffer

[kobunketsu]

My project is using GPUImage framework to process videos. Because I am using multiple frame-buffers to process image, I found GPUImageContext supportsFastTextureUpload consumes much more memory than not using it. (In 720p 15s video, supportsFastTextureUpload consumes up to 500M vs off only 200M).

So I set supportsFastTextureUpload to false in my project.But this leads to another problem. It can't handle different video formats properly.

Asset track with CVImageBufferYCbCrMatrix ITU_R_709_2 is OK.

Asset track with CVImageBufferYCbCrMatrix ITU_R_601_4 --> the result image tears.

Asset track with formatName 'avc1' --> the result image tears.

supportsFastTextureUpload can handle them correctly, but I can not avoid the memory pressure.

Why supportsFastTextureUpload=false can't not read different video frame correctly?

Or how can I solve the memory issue of supportsFastTextureUpload=true.