Compiles FFmpeg filter graphs into command-line arguments.
This module provides functionality to convert the internal DAG (Directed Acyclic Graph) representation of an FFmpeg filter chain into the actual command-line arguments that would be passed to FFmpeg. It traverses the graph in the correct order, handling global options, inputs, complex filtergraphs, and outputs.
Functions:
| Name | Description |
|---|---|
compile |
Compile a stream into a list of FFmpeg command-line arguments. |
compile(stream: Stream, auto_fix: bool = True) -> list[str]
Compile a stream into a list of FFmpeg command-line arguments.
This function takes a Stream object representing an FFmpeg filter graph and converts it into a list of command-line arguments that can be passed to FFmpeg. It processes the graph in the correct order: 1. Global nodes (general FFmpeg options) 2. Input nodes (input files and their options) 3. Filter nodes (combined into a -filter_complex argument) 4. Output nodes (output files and their options)
The function validates the graph before compilation to ensure it's properly formed. If auto_fix is enabled, it will attempt to fix common issues.
Parameters:
| Name | Type | Description | Default |
|---|---|---|---|
stream
|
Stream
|
The Stream object to compile into arguments |
required |
auto_fix
|
bool
|
Whether to automatically fix issues in the stream (e.g., reconnecting disconnected nodes) |
True
|
Returns:
| Type | Description |
|---|---|
list[str]
|
A list of strings representing FFmpeg command-line arguments |
Example
# Create a simple video scaling filter graph
input_stream = ffmpeg.input("input.mp4")
scaled = input_stream.filter("scale", 1280, 720)
output_stream = scaled.output("output.mp4")
# Compile to FFmpeg arguments
args = ffmpeg.dag.compile(output_stream)
print(
args
) # ['ffmpeg', '-i', 'input.mp4', '-filter_complex', '...', 'output.mp4']