/* SPDX-License-Identifier: GPL-2.0 */ /* * Vidtv serves as a reference DVB driver and helps validate the existing APIs * in the media subsystem. It can also aid developers working on userspace * applications. * * This file contains the code for an AES3 (also known as AES/EBU) encoder. * It is based on EBU Tech 3250 and SMPTE 302M technical documents. * * This encoder currently supports 16bit AES3 subframes using 16bit signed * integers. * * Note: AU stands for Access Unit, and AAU stands for Audio Access Unit * * Copyright (C) 2020 Daniel W. S. Almeida */ #ifndef VIDTV_S302M_H #define VIDTV_S302M_H #include <linux/types.h> #include "vidtv_encoder.h" /* see SMPTE 302M 2007 clause 7.3 */ #define VIDTV_S302M_BUF_SZ … /* see ETSI TS 102 154 v.1.2.1 clause 7.3.5 */ #define VIDTV_S302M_FORMAT_IDENTIFIER … /** * struct vidtv_s302m_ctx - s302m encoder context. * @enc: A pointer to the containing encoder structure. * @frame_index: The current frame in a block * @au_count: The total number of access units encoded up to now * @last_duration: Duration of the tone currently being played * @note_offset: Position at the music tone array * @last_tone: Tone currently being played */ struct vidtv_s302m_ctx { … }; /* * struct vidtv_smpte_s302m_es - s302m MPEG Elementary Stream header. * * See SMPTE 302M 2007 table 1. */ struct vidtv_smpte_s302m_es { … } __packed; struct vidtv_s302m_frame_16 { … } __packed; /** * struct vidtv_s302m_encoder_init_args - Args for the s302m encoder. * * @name: A name to identify this particular instance * @src_buf: The source buffer, encoder will default to a sine wave if this is NULL. * @src_buf_sz: The size of the source buffer. * @es_pid: The MPEG Elementary Stream PID to use. * @sync: Attempt to synchronize audio with this video encoder, if not NULL. * @last_sample_cb: A callback called when the encoder runs out of data. * @head: Add to this chain */ struct vidtv_s302m_encoder_init_args { … }; struct vidtv_encoder *vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args); void vidtv_s302m_encoder_destroy(struct vidtv_encoder *encoder); #endif /* VIDTV_S302M_H */