71 lines
1.8 KiB
Elixir
71 lines
1.8 KiB
Elixir
|
defmodule MPEGAudioFrameParser.Example do
|
||
|
|
require Logger
|
||
|
|
|
||
|
|
def run(path_to_mp3, block_size \\ 2048) do
|
||
|
|
# start our test process:
|
||
|
|
MPEGAudioFrameParser.start_link()
|
||
|
|
|
||
|
|
# open the provided file:
|
||
|
|
{:ok, file} = File.open(path_to_mp3, [:read, :binary])
|
||
|
|
|
||
|
|
# and start to read blocks of data:
|
||
|
|
read_bytes(file, block_size, 0, 0, 0)
|
||
|
|
end
|
||
|
|
|
||
|
|
defp read_bytes(file, block_size, total_packets, total_frames, total_bytes_processed) do
|
||
|
|
IO.binread(file, block_size)
|
||
|
|
|> handle_read(file, block_size, total_packets + 1, total_frames, total_bytes_processed)
|
||
|
|
end
|
||
|
|
|
||
|
|
defp handle_read(:eof, _file, _block_size, total_packets, total_frames, total_bytes_processed) do
|
||
|
|
Logger.info(
|
||
|
|
"End of file detected. Parsed #{total_frames} MP3 frames from #{total_packets} packets of data, total bytes processed #{
|
||
|
|
total_bytes_processed
|
||
|
|
}"
|
||
|
|
)
|
||
|
|
end
|
||
|
|
|
||
|
|
defp handle_read(
|
||
|
|
{:error, reason},
|
||
|
|
_file,
|
||
|
|
_block_size,
|
||
|
|
_total_packets,
|
||
|
|
_total_frames,
|
||
|
|
_total_bytes_processed
|
||
|
|
) do
|
||
|
|
Logger.error("Error reading file: #{reason}")
|
||
|
|
exit(:shutdown)
|
||
|
|
end
|
||
|
|
|
||
|
|
defp handle_read(data, file, block_size, total_packets, total_frames, total_bytes_processed) do
|
||
|
|
frames = MPEGAudioFrameParser.add_packet(data)
|
||
|
|
check_frames(frames)
|
||
|
|
|
||
|
|
read_bytes(
|
||
|
|
file,
|
||
|
|
block_size,
|
||
|
|
total_packets,
|
||
|
|
total_frames + length(frames),
|
||
|
|
total_byte_size(frames, total_bytes_processed)
|
||
|
|
)
|
||
|
|
end
|
||
|
|
|
||
|
|
defp check_frames([]), do: nil
|
||
|
|
|
||
|
|
defp check_frames(frames) do
|
||
|
|
[head | tail] = frames
|
||
|
|
print_frame(head)
|
||
|
|
check_frames(tail)
|
||
|
|
end
|
||
|
|
|
||
|
|
defp print_frame(_frame) do
|
||
|
|
end
|
||
|
|
|
||
|
|
defp total_byte_size([], total), do: total
|
||
|
|
|
||
|
|
defp total_byte_size(list, total) do
|
||
|
|
[head | tail] = list
|
||
|
|
total_byte_size(tail, total + byte_size(head.data))
|
||
|
|
end
|
||
|
|
end
|