Looking for the best solution for video transcoding with hardware acceleration support.

[DexerBR]

Hi, I'm searching for the best solution to transcode a video quickly and efficiently, without compromising its quality or final resolution.

The code snippet below transcodes a video using specific codecs. However, when using Android, the h264_mediacodec codecs don't seem to provide any significant improvement in encoding speed. While I can successfully create the context for h264_mediacodec for decoding, the process fails when attempting to decode the first frame, throwing an "external library error."

import av
from time import perf_counter
from av.codec.codec import dump_codecs

# print(dump_codecs())
# print(av.codecs_available)

# decode_codec = "h264_mediacodec"
# encode_codec = "h264_mediacodec"

decode_codec = "h264"
encode_codec = "libx264"

input_container = av.open(r"video_input.mp4")
input_stream = input_container.streams.video[0]

output_container = av.open("video_output.mp4", mode="w")
output_stream = output_container.add_stream(
    encode_codec,
    rate=30,
    options={"crf": "20", "preset": "ultrafast", "r": "30"},
)
output_stream.width = input_stream.width
output_stream.height = input_stream.height
output_stream.pix_fmt = "yuv420p"

ctx = av.Codec(decode_codec, "r").create()
ctx.extradata = input_stream.codec_context.extradata

start_time = perf_counter()

for packet_in in input_container.demux(input_stream):
    for frame in ctx.decode(packet_in):
        for packet_out in output_stream.encode(frame):
            output_container.mux(packet_out)

end_time = perf_counter()


for packet in output_stream.encode():
    output_container.mux(packet)

input_container.close()
output_container.close()


print("Took", end_time - start_time)

Although I’m particularly interested in the behavior on Android, I’m also curious about how it performs on desktop. This project is great, and I look forward to any assistance you can provide!

Thanks!