Zero-copy JPEG passthrough backend implementation. More...

#include "ra8_camera_codec_passthrough.h"
#include <stddef.h>
#include "ra8_attributes.h"
#include "ra8_camera_internal.h"
#include "ra8_err.h"

Include dependency graph for ra8_camera_codec_passthrough.c:

Functions
static ra8_err_t	internal_passthrough_encode (void ctx, const ra8_camera_frame_t input, const ra8_camera_buffer_t output_buffer, ra8_camera_frame_t out_frame)
	Return a JPEG input view unchanged.
ra8_err_t	ra8_camera_codec_passthrough_init (ra8_camera_codec_t *codec)
	Bind the zero-copy JPEG passthrough codec.

Variables
static const ra8_camera_codec_iface_t	s_passthrough_codec_iface
	Stateless passthrough codec vtable.

Detailed Description

Zero-copy JPEG passthrough backend implementation.

Tag: [Ring 4 / Service] {World: NS}

The codec row accepts only k_ra8_camera_format_jpeg and aliases the validated input view. It never reads or writes the supplied output buffer.

Copyright: Copyright (c) 2026 Brighton Sikarskie SPDX-License-Identifier: MIT

Since: 0.1.0

Definition in file ra8_camera_codec_passthrough.c.

Function Documentation

◆ internal_passthrough_encode()

ra8_err_t internal_passthrough_encode	(	void *	ctx,
		const ra8_camera_frame_t *	input,
		const ra8_camera_buffer_t *	output_buffer,
		ra8_camera_frame_t *	out_frame )

static

Return a JPEG input view unchanged.

Implements zero-copy encoding by aliasing an already-compressed JPEG frame and ignoring the output buffer.

Parameters

[in]	ctx	Unused stateless backend context.
[in]	input	Valid input frame.
[in]	output_buffer	Unused caller output buffer.
[out]	out_frame	Receives an alias of input.

Returns: ra8_err_t Error code.

Return values

k_ra8_ok	JPEG view returned.
k_ra8_err_null_ptr	Required frame pointer is NULL.
k_ra8_err_not_supported	Input is not JPEG.

Precondition: input passed generic frame validation.; out_frame is writable.

Postcondition: On success out_frame->data == input->data.; No input or output storage is modified.

Note: Thread-safe because the backend has no state.

Since: 0.1.0

Definition at line 46 of file ra8_camera_codec_passthrough.c.

References ra8_camera_frame_t::format, k_ra8_camera_format_jpeg, k_ra8_err_not_supported, k_ra8_err_null_ptr, k_ra8_ok, and RA8_INTERNAL.

◆ ra8_camera_codec_passthrough_init()

ra8_err_t ra8_camera_codec_passthrough_init ( ra8_camera_codec_t * codec )

nodiscard

Bind the zero-copy JPEG passthrough codec.

Parameters

[out] codec Caller-owned codec handle to bind.

Returns: ra8_err_t Error code.

Return values

k_ra8_ok	Codec bound.
k_ra8_err_null_ptr	codec was NULL.

Precondition: codec out-lives every codec operation.; The caller does not mutate the handle while encoding.

Postcondition: On success JPEG input is returned byte-for-byte without copying.; On error no state is modified.

Note: Stateless; independent handles are thread-safe.

Since: 0.1.0

Definition at line 71 of file ra8_camera_codec_passthrough.c.

References ra8_camera_codec_t::ctx, ra8_camera_codec_t::iface, k_ra8_err_null_ptr, k_ra8_ok, and s_passthrough_codec_iface.

Referenced by internal_bring_up_capture_pipeline().

Variable Documentation

◆ s_passthrough_codec_iface

const ra8_camera_codec_iface_t s_passthrough_codec_iface

static

Initial value:

                                                                = {
  .encode = internal_passthrough_encode,
}

Stateless passthrough codec vtable.

Definition at line 67 of file ra8_camera_codec_passthrough.c.

Referenced by ra8_camera_codec_passthrough_init().