1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */ 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * Vidtv serves as a reference DVB driver and helps validate the existing APIs 4*4882a593Smuzhiyun * in the media subsystem. It can also aid developers working on userspace 5*4882a593Smuzhiyun * applications. 6*4882a593Smuzhiyun * 7*4882a593Smuzhiyun * This file contains the code for an AES3 (also known as AES/EBU) encoder. 8*4882a593Smuzhiyun * It is based on EBU Tech 3250 and SMPTE 302M technical documents. 9*4882a593Smuzhiyun * 10*4882a593Smuzhiyun * This encoder currently supports 16bit AES3 subframes using 16bit signed 11*4882a593Smuzhiyun * integers. 12*4882a593Smuzhiyun * 13*4882a593Smuzhiyun * Note: AU stands for Access Unit, and AAU stands for Audio Access Unit 14*4882a593Smuzhiyun * 15*4882a593Smuzhiyun * Copyright (C) 2020 Daniel W. S. Almeida 16*4882a593Smuzhiyun */ 17*4882a593Smuzhiyun 18*4882a593Smuzhiyun #ifndef VIDTV_S302M_H 19*4882a593Smuzhiyun #define VIDTV_S302M_H 20*4882a593Smuzhiyun 21*4882a593Smuzhiyun #include <linux/types.h> 22*4882a593Smuzhiyun 23*4882a593Smuzhiyun #include "vidtv_encoder.h" 24*4882a593Smuzhiyun 25*4882a593Smuzhiyun /* see SMPTE 302M 2007 clause 7.3 */ 26*4882a593Smuzhiyun #define VIDTV_S302M_BUF_SZ 65024 27*4882a593Smuzhiyun 28*4882a593Smuzhiyun /* see ETSI TS 102 154 v.1.2.1 clause 7.3.5 */ 29*4882a593Smuzhiyun #define VIDTV_S302M_FORMAT_IDENTIFIER 0x42535344 30*4882a593Smuzhiyun 31*4882a593Smuzhiyun /** 32*4882a593Smuzhiyun * struct vidtv_s302m_ctx - s302m encoder context. 33*4882a593Smuzhiyun * @enc: A pointer to the containing encoder structure. 34*4882a593Smuzhiyun * @frame_index: The current frame in a block 35*4882a593Smuzhiyun * @au_count: The total number of access units encoded up to now 36*4882a593Smuzhiyun * @last_duration: Duration of the tone currently being played 37*4882a593Smuzhiyun * @note_offset: Position at the music tone array 38*4882a593Smuzhiyun * @last_tone: Tone currently being played 39*4882a593Smuzhiyun */ 40*4882a593Smuzhiyun struct vidtv_s302m_ctx { 41*4882a593Smuzhiyun struct vidtv_encoder *enc; 42*4882a593Smuzhiyun u32 frame_index; 43*4882a593Smuzhiyun u32 au_count; 44*4882a593Smuzhiyun int last_duration; 45*4882a593Smuzhiyun unsigned int note_offset; 46*4882a593Smuzhiyun enum musical_notes last_tone; 47*4882a593Smuzhiyun }; 48*4882a593Smuzhiyun 49*4882a593Smuzhiyun /* 50*4882a593Smuzhiyun * struct vidtv_smpte_s302m_es - s302m MPEG Elementary Stream header. 51*4882a593Smuzhiyun * 52*4882a593Smuzhiyun * See SMPTE 302M 2007 table 1. 53*4882a593Smuzhiyun */ 54*4882a593Smuzhiyun struct vidtv_smpte_s302m_es { 55*4882a593Smuzhiyun /* 56*4882a593Smuzhiyun * 57*4882a593Smuzhiyun * audio_packet_size:16; 58*4882a593Smuzhiyun * num_channels:2; 59*4882a593Smuzhiyun * channel_identification:8; 60*4882a593Smuzhiyun * bits_per_sample:2; // 0x0 for 16bits 61*4882a593Smuzhiyun * zero:4; 62*4882a593Smuzhiyun */ 63*4882a593Smuzhiyun __be32 bitfield; 64*4882a593Smuzhiyun } __packed; 65*4882a593Smuzhiyun 66*4882a593Smuzhiyun struct vidtv_s302m_frame_16 { 67*4882a593Smuzhiyun u8 data[5]; 68*4882a593Smuzhiyun } __packed; 69*4882a593Smuzhiyun 70*4882a593Smuzhiyun /** 71*4882a593Smuzhiyun * struct vidtv_s302m_encoder_init_args - Args for the s302m encoder. 72*4882a593Smuzhiyun * 73*4882a593Smuzhiyun * @name: A name to identify this particular instance 74*4882a593Smuzhiyun * @src_buf: The source buffer, encoder will default to a sine wave if this is NULL. 75*4882a593Smuzhiyun * @src_buf_sz: The size of the source buffer. 76*4882a593Smuzhiyun * @es_pid: The MPEG Elementary Stream PID to use. 77*4882a593Smuzhiyun * @sync: Attempt to synchronize audio with this video encoder, if not NULL. 78*4882a593Smuzhiyun * @last_sample_cb: A callback called when the encoder runs out of data. 79*4882a593Smuzhiyun * @head: Add to this chain 80*4882a593Smuzhiyun */ 81*4882a593Smuzhiyun struct vidtv_s302m_encoder_init_args { 82*4882a593Smuzhiyun char *name; 83*4882a593Smuzhiyun void *src_buf; 84*4882a593Smuzhiyun u32 src_buf_sz; 85*4882a593Smuzhiyun u16 es_pid; 86*4882a593Smuzhiyun struct vidtv_encoder *sync; 87*4882a593Smuzhiyun void (*last_sample_cb)(u32 sample_no); 88*4882a593Smuzhiyun 89*4882a593Smuzhiyun struct vidtv_encoder *head; 90*4882a593Smuzhiyun }; 91*4882a593Smuzhiyun 92*4882a593Smuzhiyun struct vidtv_encoder 93*4882a593Smuzhiyun *vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args); 94*4882a593Smuzhiyun 95*4882a593Smuzhiyun void vidtv_s302m_encoder_destroy(struct vidtv_encoder *encoder); 96*4882a593Smuzhiyun 97*4882a593Smuzhiyun #endif /* VIDTV_S302M_H */ 98