Nvidia codec SDK samples: can't decode an encoded file correctly - sdk

Question

I'm trying out the sample applications in the Nvidia video codec sdk, and am having trouble getting a useable decoded result.
My input file is YUV 4:2:0, taken from here, which is 352x288px.
I'm encoding using the AppEncD3D12.exe sample, with the following command:
.\AppEncD3D12.exe -i D:\akiyo_cif.y4m -s 352x288 -o D:\akiyo_out.mp4
This gives the output
GPU in use: NVIDIA GeForce RTX 2080 Super with Max-Q Design
[INFO ][17:46:39] Encoding Parameters:
codec : h264
preset : p3
tuningInfo : hq
profile : (default)
chroma : yuv420
bitdepth : 8
rc : vbr
fps : 30/1
gop : 250
bf : 1
multipass : 0
size : 352x288
bitrate : 0
maxbitrate : 0
vbvbufsize : 0
vbvinit : 0
aq : disabled
temporalaq : disabled
lookahead : disabled
cq : 0
qmin : P,B,I=0,0,0
qmax : P,B,I=0,0,0
initqp : P,B,I=0,0,0
Total frames encoded: 112
Saved in file D:\akiyo_out.mp4
Which looks promising. However, using the decode sample, a single frame of the output contains what look like 12 smaller frames of the input, in monochrome.
I'm running the decode sample like this:
PS D:\Nvidia\Video_Codec_SDK_11.1.5\Samples\build\Debug> .\AppDecD3D.exe -i D:\akiyo_out.mp4
GPU in use: NVIDIA GeForce RTX 2080 Super with Max-Q Design
Display with D3D9.
[INFO ][17:58:58] Media format: raw H.264 video (h264)
Session Initialization Time: 23 ms
[INFO ][17:58:58] Video Input Information
Codec : AVC/H.264
Frame rate : 30000/1000 = 30 fps
Sequence : Progressive
Coded size : [352, 288]
Display area : [0, 0, 352, 288]
Chroma : YUV 420
Bit depth : 8
Video Decoding Params:
Num Surfaces : 7
Crop : [0, 0, 0, 0]
Resize : 352x288
Deinterlace : Weave
Total frame decoded: 112
Session Deinitialization Time: 8 ms
I'm quite new to this so could be doing something stupid. Right now I don't know whether to look at encode or decode! Any ideas or tips most appreciated.
-I've tried other YUV files with the same result. I read that 4:2:2 is not supported, the above is 4:2:0.
Using the AppEncCuda sample, the decoded video (played with AppDecD3D.exe) is the correct size and in colour, but the video appears to scroll to the right as it is played, with colour information not scrolling at the same rate as the image

Answer 1

you have 2 problems:
According to the code and remarks in the AppEncD3D12 sample it expect the input frames to be in ARGB format but your input file is YUV -so the sample read data from the YUV file and treat it as ARGB. If you want the AppEncD3D12 to work with this file you need to either convert each YUV frame to argb or to change the code to work with YUV as input. The AppEncCuda sample is expecting YUV as input and that is the reason it give you better results. you can also see that in the AppEncD3D12 there were a total of 112 encoded but in the AppEncCuda there a total of 300 frames - this is because YUV frame are smaller then ARGB frames.
the 2nd problem is that the both sample save the output as RAW h264. The file is not really MP4 despite the name you gave it. There are a few players that can play a file of h264 RAW data and you can try to use them to play the output file. another option is to use FFMPEG to create a valid MP4 file and pass the RAW h264 samples to it - the NVIDIA encoder encode the video but it does not handle the creation of video files containers (There 2 many type of files like avi,mpg,mp4,mkv,ts, etc.) - you should use FFMPEG or other solution for that. The sdk samples contain a file FFmpegStreamer.h under the Utils folder that show how to use ffmpeg to output h264 video in Mpeg2 transport stream format to a file (*.ts) or the network.