cbs.cpp File Reference

Definitions for FFmpeg Coded Bitstream API. More...

#include <libavcodec/avcodec.h>
#include <libavcodec/cbs_h264.h>
#include <libavcodec/cbs_h265.h>
#include <libavcodec/h264_levels.h>
#include <libavutil/pixdesc.h>
#include "cbs.h"
#include "logging.h"
#include "utility.h"

Include dependency graph for cbs.cpp:

Classes
class	cbs::frag_t
	Owns an FFmpeg coded bitstream fragment and frees fragment buffers on destruction. More...

Typedefs
using	cbs::ctx_t = util::safe_ptr<CodedBitstreamContext, close>
	Owning coded bitstream context pointer that calls ff_cbs_close.

Functions
void	cbs::close (CodedBitstreamContext *c)
	Release an FFmpeg coded bitstream context.
h264_t	cbs::make_sps_h264 (const AVCodecContext *avctx, const AVPacket *packet)
	Build replacement H.264 SPS bytes with Sunshine-required VUI fields.
hevc_t	cbs::make_sps_hevc (const AVCodecContext *avctx, const AVPacket *packet)
	Build replacement HEVC VPS/SPS bytes with Sunshine-required VUI fields.
bool	cbs::validate_sps (const AVPacket *packet, int codec_id)
	Check whether an encoded H.264 or HEVC packet contains active SPS VUI metadata.
util::buffer_t< std::uint8_t >	cbs::write (cbs::ctx_t &cbs_ctx, std::uint8_t nal, void *uh, AVCodecID codec_id)
	Serialize a prepared coded bitstream unit with an existing context.
util::buffer_t< std::uint8_t >	cbs::write (std::uint8_t nal, void *uh, AVCodecID codec_id)
	Serialize a prepared coded bitstream unit with a temporary context.

Detailed Description

Definitions for FFmpeg Coded Bitstream API.

Function Documentation

close()

void cbs::close

(

CodedBitstreamContext *

c

)

Release an FFmpeg coded bitstream context.

Parameters

c	Context pointer owned by the safe pointer wrapper.

make_sps_h264()

h264_t cbs::make_sps_h264	(	const AVCodecContext *	ctx,
		const AVPacket *	packet )

Build replacement H.264 SPS bytes with Sunshine-required VUI fields.

Build an H.264 replacement SPS for a packet.

Parameters

ctx	FFmpeg codec context that provides colorimetry and reference-frame metadata.
packet	Encoded packet containing the original SPS.

Returns

Original and rewritten SPS bytes.

make_sps_hevc()

hevc_t cbs::make_sps_hevc	(	const AVCodecContext *	ctx,
		const AVPacket *	packet )

Build replacement HEVC VPS/SPS bytes with Sunshine-required VUI fields.

Build HEVC replacement parameter sets for a packet.

Parameters

ctx	FFmpeg codec context that provides colorimetry and reference-frame metadata.
packet	Encoded packet containing the original VPS and SPS.

Returns

Original and rewritten VPS/SPS bytes.

validate_sps()

bool cbs::validate_sps	(	const AVPacket *	packet,
		int	codec_id )

Check whether an encoded H.264 or HEVC packet contains active SPS VUI metadata.

Parameters

packet	Encoded packet to parse with FFmpeg's coded bitstream reader.
codec_id	FFmpeg codec identifier; expected to be AV_CODEC_ID_H264 or AV_CODEC_ID_H265.

Returns

true when the packet's active SPS advertises VUI parameters.

write() [1/2]

util::buffer_t< std::uint8_t > cbs::write	(	cbs::ctx_t &	cbs_ctx,
		std::uint8_t	nal,
		void *	uh,
		AVCodecID	codec_id )

Serialize a prepared coded bitstream unit with an existing context.

Parameters

cbs_ctx	Coded bitstream context initialized for the codec.
nal	NAL unit type to insert into the fragment.
uh	Pointer to the FFmpeg raw unit header/content structure.
codec_id	FFmpeg codec identifier used by the context.

Returns

Serialized NAL unit bytes, or an empty buffer if FFmpeg rejects the fragment.

write() [2/2]

util::buffer_t< std::uint8_t > cbs::write	(	std::uint8_t	nal,
		void *	uh,
		AVCodecID	codec_id )

Serialize a prepared coded bitstream unit with a temporary context.

Parameters

nal	NAL unit type to insert into the fragment.
uh	Pointer to the FFmpeg raw unit header/content structure.
codec_id	FFmpeg codec identifier used to initialize the temporary context.

Returns

Serialized NAL unit bytes, or an empty buffer if FFmpeg rejects the fragment.