BufferList

class BufferList(**kwargs)

Buffer lists are an object containing a list of buffers.

Buffer lists are created with new() and filled with data using insert().

Buffer lists can be pushed on a srcpad with push_list(). This is interesting when multiple buffers need to be pushed in one go because it can reduce the amount of overhead for pushing each buffer individually.

Constructors

class BufferList
classmethod new() → BufferList

Creates a new, empty BufferList.

classmethod new_sized(size: int) → BufferList

Creates a new, empty BufferList. The list will have size space preallocated so that memory reallocations can be avoided.

Parameters:

size – an initial reserved size

Methods

class BufferList
calculate_size() → int

Calculates the size of the data contained in list by adding the size of all buffers.

Added in version 1.14.

foreach(func: Callable[[...], tuple[bool, Buffer]], *user_data: Any) → bool

Calls func with data for each buffer in list.

func can modify the passed buffer pointer or its contents. The return value of func defines if this function returns or if the remaining buffers in the list should be skipped.

Parameters:

  • func – a BufferListFunc to call

  • user_data – user data passed to func

get(idx: int) → Buffer | None

Gets the buffer at idx.

You must make sure that idx does not exceed the number of buffers available.

Parameters:

idx – the index

get_writable(idx: int) → Buffer | None

Gets the buffer at idx, ensuring it is a writable buffer.

You must make sure that idx does not exceed the number of buffers available.

Added in version 1.14.

Parameters:

idx – the index

insert(idx: int, buffer: Buffer) → None

Inserts buffer at idx in list. Other buffers are moved to make room for this new buffer.

A -1 value for idx will append the buffer at the end.

Parameters:

  • idx – the index

  • buffer – a Buffer

length() → int

Returns the number of buffers in list.

remove(idx: int, length: int) → None

Removes length buffers starting from idx in list. The following buffers are moved to close the gap.

Parameters:

  • idx – the index

  • length – the amount to remove