Decode raw h264 file and convert into mp4

I have a raw video file(lets say raw.h264). I would like to decode and convert into mp4.

I tried to use :
ops.VideoReader(device = "gpu", filenames = data, sequence_length = sequence_length,
shard_id = 0, num_shards = 1,
random_shuffle = shuffle, initial_fill = initial_prefetch_size,channels=3)
But it does not read the raw file.
I thought of trying ExternalSource, but even if I read with external source pipeline, the dali has in-built decoder in VideoReader. I did not find any ops that I can use to decode after importing file using ExternalSource.

Could anyone help me in find the solution on how to decode the raw h.264 format file.
This operation is simple in ffmpeg, but I want to try with dali.
The ffmpeg example:
ffmpeg.input('raw.h264', format='h264').output('pipe:', format='rawvideo', pix_fmt='uyvy422')

Start with the VideoReader and ExternalSource entry points mentioned in the report, and compare their supported inputs with the ffmpeg h264 example. Done means establishing whether DALI supports decoding a raw h264 file and, if so, demonstrating a reproducible pipeline that produces the requested video output.