def call_vmaf(chunk: Chunk,
encoded: Path,
n_threads,
model,
res,
fl_path: Path = None,
vmaf_filter=None,
vmaf_rate=0):
cmd = ''
# settings model path
mod = f":model_path={model}" if model else ''
# limiting amount of threads for calculation
n_threads = f':n_threads={n_threads}' if n_threads else ''
if fl_path is None:
fl_path = chunk.fake_input_path.with_name(
encoded.stem).with_suffix('.json')
fl = fl_path.as_posix()
filter = vmaf_filter + ',' if vmaf_filter else ''
# For vmaf calculation both source and encoded segment scaled to 1080
# Also it's required to use -r before both files of vmaf calculation to avoid errors
cmd_in = ('ffmpeg', '-loglevel', 'info', '-y',
'-thread_queue_size', '1024', '-hide_banner', '-r', '60', '-i',
encoded.as_posix(), '-r', '60', '-i', '-')
filter_complex = ('-filter_complex', )
# Change framerate of comparison to framerate of probe
select_frames = f"select=not(mod(n\\,{vmaf_rate}))," if vmaf_rate != 0 else ''
distorted = f'[0:v]{select_frames}scale={res}:flags=bicubic:\
force_original_aspect_ratio=decrease,setpts=PTS-STARTPTS[distorted];'
ref = fr'[1:v]{select_frames}{filter}scale={res}:flags=bicubic:'\
'force_original_aspect_ratio=decrease,setpts=PTS-STARTPTS[ref];'
vmaf_filter = f"[distorted][ref]libvmaf=log_fmt='json':eof_action=endall:\
log_path={shlex.quote(fl)}{mod}{n_threads}"
cmd_out = ('-f', 'null', '-')
cmd = (*cmd_in, *filter_complex, distorted + ref + vmaf_filter, *cmd_out)
ffmpeg_gen_pipe = subprocess.Popen(chunk.ffmpeg_gen_cmd,
stdout=PIPE,
stderr=STDOUT)
pipe = subprocess.Popen(cmd,
stdin=ffmpeg_gen_pipe.stdout,
stdout=PIPE,
stderr=STDOUT,
universal_newlines=True)
process_pipe(pipe)
return fl_path
def per_frame_probe(q_list, q, chunk, project):
qfile = chunk.make_q_file(q_list)
cmd = per_frame_probe_cmd(chunk, q, project.ffmpeg_pipe, project.encoder,
1, qfile)
pipe = make_pipes(chunk.ffmpeg_gen_cmd, cmd)
process_pipe(pipe, chunk)
fl = call_vmaf(chunk,
gen_probes_names(chunk, q),
project.n_threads,
project.vmaf_path,
project.vmaf_res,
vmaf_filter=project.vmaf_filter,
vmaf_rate=1)
jsn = read_json(fl)
vmafs = [x['metrics']['vmaf'] for x in jsn['frames']]
return vmafs
def vmaf_probe(chunk: Chunk, q, args: Project, probing_rate):
"""
Calculates vmaf and returns path to json file
:param chunk: the Chunk
:param q: Value to make probe
:param args: the Project
:return : path to json file with vmaf scores
"""
cmd = probe_cmd(chunk, q, args.ffmpeg_pipe, args.encoder, probing_rate)
pipe = make_pipes(chunk.ffmpeg_gen_cmd, cmd)
process_pipe(pipe, chunk)
file = call_vmaf(chunk, gen_probes_names(chunk, q), args.n_threads, args.vmaf_path, args.vmaf_res, vmaf_filter=args.vmaf_filter,
vmaf_rate=probing_rate)
return file
def vmaf_probe(chunk: Chunk, q, args: Args):
"""
Make encoding probe to get VMAF that Q returns
:param chunk: the Chunk
:param q: Value to make probe
:param args: the Args
:return :
"""
cmd = probe_cmd(chunk, q, args.ffmpeg_pipe, args.encoder, args.vmaf_rate)
pipe = make_pipes(chunk.ffmpeg_gen_cmd, cmd)
process_pipe(pipe)
file = call_vmaf(chunk, gen_probes_names(chunk, q), args.n_threads, args.vmaf_path, args.vmaf_res, vmaf_filter=args.vmaf_filter,
vmaf_rate=args.vmaf_rate)
score = read_vmaf_json(file, 20)
return score
