jpeg_transport.h File Reference

An RTP/JPEG data transport. More...

#include <compy/droppable.h>
#include <compy/rtp_transport.h>
#include <stdbool.h>
#include <stddef.h>
#include <slice99.h>
#include <compy/priv/compiler_attrs.h>

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Data Structures
struct	Compy_JpegTransportConfig
	The configuration structure for Compy_JpegTransport. More...

Macros
#define	COMPY_JPEG_DEFAULT_MAX_FRAGMENT_SIZE   1200
	The default value for Compy_JpegTransportConfig.max_fragment_size.

Typedefs
typedef struct Compy_JpegTransport	Compy_JpegTransport
	An RTP/JPEG data transport.

Functions
Compy_JpegTransportConfig	Compy_JpegTransportConfig_default (void) COMPY_PRIV_MUST_USE
	Returns the default Compy_JpegTransportConfig.
Compy_JpegTransport *	Compy_JpegTransport_new (Compy_RtpTransport *t) COMPY_PRIV_MUST_USE
	Creates a new RTP/JPEG transport with the default configuration.
Compy_JpegTransport *	Compy_JpegTransport_new_with_config (Compy_RtpTransport *t, Compy_JpegTransportConfig config) COMPY_PRIV_MUST_USE
	Creates a new RTP/JPEG transport with a custom configuration.
int	Compy_JpegTransport_send_frame (Compy_JpegTransport *self, Compy_RtpTimestamp ts, U8Slice99 jpeg_frame) COMPY_PRIV_MUST_USE
	Sends a complete JPEG frame as one or more RTP packets.
bool	Compy_JpegTransport_is_full (Compy_JpegTransport *self)
	Returns whether the underlying transport's send buffer is full.
	declImplExtern99 (Compy_Droppable, Compy_JpegTransport)
	Implements Compy_Droppable_IFACE for Compy_JpegTransport.

Detailed Description

An RTP/JPEG data transport.

Packetizes baseline JPEG frames into RTP packets per RFC 2435. Supports YUV 4:2:0 and 4:2:2 subsampling, custom quantization tables (Q=255), and restart marker intervals (DRI).

See also

RTP Payload Format for JPEG-compressed Video: https://datatracker.ietf.org/doc/html/rfc2435

Function Documentation

Compy_JpegTransport_is_full()

bool Compy_JpegTransport_is_full

(

Compy_JpegTransport *

self

)

Returns whether the underlying transport's send buffer is full.

Precondition

self != NULL

Compy_JpegTransport_new()

Compy_JpegTransport * Compy_JpegTransport_new

(

Compy_RtpTransport *

t

)

Creates a new RTP/JPEG transport with the default configuration.

Parameters

[in]

t

The underlying RTP transport (payload type 26, clock 90000 Hz).

Precondition

t != NULL

Compy_JpegTransport_new_with_config()

Compy_JpegTransport * Compy_JpegTransport_new_with_config	(	Compy_RtpTransport *	t,
		Compy_JpegTransportConfig	config
	)

Creates a new RTP/JPEG transport with a custom configuration.

Parameters

[in]	t	The underlying RTP transport (payload type 26, clock 90000 Hz).
[in]	config	The transmission configuration structure.

Precondition

t != NULL

Compy_JpegTransport_send_frame()

int Compy_JpegTransport_send_frame	(	Compy_JpegTransport *	self,
		Compy_RtpTimestamp	ts,
		U8Slice99	jpeg_frame
	)

Sends a complete JPEG frame as one or more RTP packets.

The frame is parsed to extract dimensions, quantization tables, and scan data. Scan data is fragmented according to the configured max_fragment_size. The RTP marker bit is set on the last fragment.

Only baseline DCT JPEG (SOF0) is supported. Custom quantization tables are always sent in-band (Q=255 per RFC 2435 Section 3.1.8).

Parameters

[out]	self	The RTP/JPEG transport.
[in]	ts	The RTP timestamp for this frame.
[in]	jpeg_frame	The complete JPEG frame (SOI through EOI).

Precondition

self != NULL

Returns

-1 if an I/O or parse error occurred, 0 on success.

Compy_JpegTransportConfig_default()

Compy_JpegTransportConfig Compy_JpegTransportConfig_default

(

void

)

Returns the default Compy_JpegTransportConfig.

The default values are:

• max_fragment_size is COMPY_JPEG_DEFAULT_MAX_FRAGMENT_SIZE.

declImplExtern99()

declImplExtern99	(	Compy_Droppable	,
		Compy_JpegTransport
	)

Implements Compy_Droppable_IFACE for Compy_JpegTransport.

See Interface99 for the macro usage.