diff options
Diffstat (limited to 'drivers/media/test-drivers/vidtv/vidtv_s302m.h')
-rw-r--r-- | drivers/media/test-drivers/vidtv/vidtv_s302m.h | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.h b/drivers/media/test-drivers/vidtv/vidtv_s302m.h new file mode 100644 index 000000000..9cc94e4a8 --- /dev/null +++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.h @@ -0,0 +1,97 @@ +/* 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 65024 + +/* see ETSI TS 102 154 v.1.2.1 clause 7.3.5 */ +#define VIDTV_S302M_FORMAT_IDENTIFIER 0x42535344 + +/** + * 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_encoder *enc; + u32 frame_index; + u32 au_count; + int last_duration; + unsigned int note_offset; + enum musical_notes last_tone; +}; + +/* + * struct vidtv_smpte_s302m_es - s302m MPEG Elementary Stream header. + * + * See SMPTE 302M 2007 table 1. + */ +struct vidtv_smpte_s302m_es { + /* + * + * audio_packet_size:16; + * num_channels:2; + * channel_identification:8; + * bits_per_sample:2; // 0x0 for 16bits + * zero:4; + */ + __be32 bitfield; +} __packed; + +struct vidtv_s302m_frame_16 { + u8 data[5]; +} __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 { + char *name; + void *src_buf; + u32 src_buf_sz; + u16 es_pid; + struct vidtv_encoder *sync; + void (*last_sample_cb)(u32 sample_no); + + struct vidtv_encoder *head; +}; + +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 */ |