blob: d79b65854627cc18c60c5172430c40369e687c68 [file] [log] [blame]
// 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
*/
#define pr_fmt(fmt) KBUILD_MODNAME ":%s, %d: " fmt, __func__, __LINE__
#include <linux/bug.h>
#include <linux/crc32.h>
#include <linux/fixp-arith.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/printk.h>
#include <linux/ratelimit.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/vmalloc.h>
#include "vidtv_common.h"
#include "vidtv_encoder.h"
#include "vidtv_s302m.h"
#define S302M_SAMPLING_RATE_HZ 48000
#define PES_PRIVATE_STREAM_1 0xbd /* PES: private_stream_1 */
#define S302M_BLOCK_SZ 192
#define S302M_SIN_LUT_NUM_ELEM 1024
/* these are retrieved empirically from ffmpeg/libavcodec */
#define FF_S302M_DEFAULT_NUM_FRAMES 1115
#define FF_S302M_DEFAULT_PTS_INCREMENT 2090
#define FF_S302M_DEFAULT_PTS_OFFSET 100000
/* Used by the tone generator: number of samples for PI */
#define PI 180
static const u8 reverse[256] = {
/* from ffmpeg */
0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0,
0x30, 0xB0, 0x70, 0xF0, 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, 0x04, 0x84, 0x44, 0xC4,
0x24, 0xA4, 0x64, 0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC,
0x3C, 0xBC, 0x7C, 0xFC, 0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, 0x0A, 0x8A, 0x4A, 0xCA,
0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, 0x16, 0x96, 0x56, 0xD6,
0x36, 0xB6, 0x76, 0xF6, 0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, 0x01, 0x81, 0x41, 0xC1,
0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9,
0x39, 0xB9, 0x79, 0xF9, 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, 0x0D, 0x8D, 0x4D, 0xCD,
0x2D, 0xAD, 0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3,
0x33, 0xB3, 0x73, 0xF3, 0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, 0x07, 0x87, 0x47, 0xC7,
0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, 0x1F, 0x9F, 0x5F, 0xDF,
0x3F, 0xBF, 0x7F, 0xFF,
};
struct tone_duration {
enum musical_notes note;
int duration;
};
#define COMPASS 100 /* beats per minute */
static const struct tone_duration beethoven_fur_elise[] = {
{ NOTE_SILENT, 512},
{ NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},
{ NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},
{ NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},
{ NOTE_GS_5, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_5, 128},
{ NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},
{ NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},
{ NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},
{ NOTE_C_6, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_SILENT, 128},
{ NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},
{ NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},
{ NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},
{ NOTE_GS_5, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_5, 128},
{ NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},
{ NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},
{ NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},
{ NOTE_C_6, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_B_4, 128},
{ NOTE_C_5, 128}, { NOTE_D_5, 128}, { NOTE_C_4, 128},
{ NOTE_G_4, 128}, { NOTE_C_5, 128}, { NOTE_G_4, 128},
{ NOTE_F_5, 128}, { NOTE_E_5, 128}, { NOTE_G_3, 128},
{ NOTE_G_4, 128}, { NOTE_B_3, 128}, { NOTE_F_4, 128},
{ NOTE_E_5, 128}, { NOTE_D_5, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_4, 128},
{ NOTE_D_5, 128}, { NOTE_C_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_E_5, 128}, { NOTE_E_5, 128},
{ NOTE_E_6, 128}, { NOTE_E_5, 128}, { NOTE_E_6, 128},
{ NOTE_E_5, 128}, { NOTE_E_5, 128}, { NOTE_DS_5, 128},
{ NOTE_E_5, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_5, 128}, { NOTE_E_5, 128}, { NOTE_DS_6, 128},
{ NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},
{ NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},
{ NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},
{ NOTE_GS_5, 128}, { NOTE_B_5, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_E_5, 128},
{ NOTE_E_6, 128}, { NOTE_DS_6, 128}, { NOTE_E_6, 128},
{ NOTE_DS_6, 128}, { NOTE_E_6, 128}, { NOTE_B_5, 128},
{ NOTE_D_6, 128}, { NOTE_C_6, 128}, { NOTE_A_3, 128},
{ NOTE_E_4, 128}, { NOTE_A_4, 128}, { NOTE_C_5, 128},
{ NOTE_E_5, 128}, { NOTE_A_5, 128}, { NOTE_E_3, 128},
{ NOTE_E_4, 128}, { NOTE_GS_4, 128}, { NOTE_E_5, 128},
{ NOTE_C_6, 128}, { NOTE_B_5, 128}, { NOTE_A_5, 512},
{ NOTE_SILENT, 256},
};
static struct vidtv_access_unit *vidtv_s302m_access_unit_init(struct vidtv_access_unit *head)
{
struct vidtv_access_unit *au;
au = kzalloc(sizeof(*au), GFP_KERNEL);
if (!au)
return NULL;
if (head) {
while (head->next)
head = head->next;
head->next = au;
}
return au;
}
static void vidtv_s302m_access_unit_destroy(struct vidtv_encoder *e)
{
struct vidtv_access_unit *head = e->access_units;
struct vidtv_access_unit *tmp = NULL;
while (head) {
tmp = head;
head = head->next;
kfree(tmp);
}
e->access_units = NULL;
}
static void vidtv_s302m_alloc_au(struct vidtv_encoder *e)
{
struct vidtv_access_unit *sync_au = NULL;
struct vidtv_access_unit *temp = NULL;
if (e->sync && e->sync->is_video_encoder) {
sync_au = e->sync->access_units;
while (sync_au) {
temp = vidtv_s302m_access_unit_init(e->access_units);
if (!e->access_units)
e->access_units = temp;
sync_au = sync_au->next;
}
return;
}
e->access_units = vidtv_s302m_access_unit_init(NULL);
}
static void
vidtv_s302m_compute_sample_count_from_video(struct vidtv_encoder *e)
{
struct vidtv_access_unit *sync_au = e->sync->access_units;
struct vidtv_access_unit *au = e->access_units;
u32 sample_duration_usecs;
u32 vau_duration_usecs;
u32 s;
vau_duration_usecs = USEC_PER_SEC / e->sync->sampling_rate_hz;
sample_duration_usecs = USEC_PER_SEC / e->sampling_rate_hz;
while (au && sync_au) {
s = DIV_ROUND_UP(vau_duration_usecs, sample_duration_usecs);
au->num_samples = s;
au = au->next;
sync_au = sync_au->next;
}
}
static void vidtv_s302m_compute_pts_from_video(struct vidtv_encoder *e)
{
struct vidtv_access_unit *au = e->access_units;
struct vidtv_access_unit *sync_au = e->sync->access_units;
/* use the same pts from the video access unit*/
while (au && sync_au) {
au->pts = sync_au->pts;
au = au->next;
sync_au = sync_au->next;
}
}
static u16 vidtv_s302m_get_sample(struct vidtv_encoder *e)
{
u16 sample;
int pos;
struct vidtv_s302m_ctx *ctx = e->ctx;
if (!e->src_buf) {
/*
* Simple tone generator: play the tones at the
* beethoven_fur_elise array.
*/
if (ctx->last_duration <= 0) {
if (e->src_buf_offset >= ARRAY_SIZE(beethoven_fur_elise))
e->src_buf_offset = 0;
ctx->last_tone = beethoven_fur_elise[e->src_buf_offset].note;
ctx->last_duration = beethoven_fur_elise[e->src_buf_offset].duration *
S302M_SAMPLING_RATE_HZ / COMPASS / 5;
e->src_buf_offset++;
ctx->note_offset = 0;
} else {
ctx->last_duration--;
}
/* Handle pause notes */
if (!ctx->last_tone)
return 0x8000;
pos = (2 * PI * ctx->note_offset * ctx->last_tone) / S302M_SAMPLING_RATE_HZ;
ctx->note_offset++;
return (fixp_sin32(pos % (2 * PI)) >> 16) + 0x8000;
}
/* bug somewhere */
if (e->src_buf_offset > e->src_buf_sz) {
pr_err_ratelimited("overflow detected: %d > %d, wrapping.\n",
e->src_buf_offset,
e->src_buf_sz);
e->src_buf_offset = 0;
}
if (e->src_buf_offset >= e->src_buf_sz) {
/* let the source know we are out of data */
if (e->last_sample_cb)
e->last_sample_cb(e->sample_count);
e->src_buf_offset = 0;
}
sample = *(u16 *)(e->src_buf + e->src_buf_offset);
return sample;
}
static u32 vidtv_s302m_write_frame(struct vidtv_encoder *e,
u16 sample)
{
struct vidtv_s302m_ctx *ctx = e->ctx;
struct vidtv_s302m_frame_16 f = {};
u32 nbytes = 0;
/* from ffmpeg: see s302enc.c */
u8 vucf = ctx->frame_index == 0 ? 0x10 : 0;
f.data[0] = sample & 0xFF;
f.data[1] = (sample & 0xFF00) >> 8;
f.data[2] = ((sample & 0x0F) << 4) | vucf;
f.data[3] = (sample & 0x0FF0) >> 4;
f.data[4] = (sample & 0xF000) >> 12;
f.data[0] = reverse[f.data[0]];
f.data[1] = reverse[f.data[1]];
f.data[2] = reverse[f.data[2]];
f.data[3] = reverse[f.data[3]];
f.data[4] = reverse[f.data[4]];
nbytes += vidtv_memcpy(e->encoder_buf,
e->encoder_buf_offset,
VIDTV_S302M_BUF_SZ,
&f,
sizeof(f));
e->encoder_buf_offset += nbytes;
ctx->frame_index++;
if (ctx->frame_index >= S302M_BLOCK_SZ)
ctx->frame_index = 0;
return nbytes;
}
static u32 vidtv_s302m_write_h(struct vidtv_encoder *e, u32 p_sz)
{
struct vidtv_smpte_s302m_es h = {};
u32 nbytes = 0;
/* 2 channels, ident: 0, 16 bits per sample */
h.bitfield = cpu_to_be32((p_sz << 16));
nbytes += vidtv_memcpy(e->encoder_buf,
e->encoder_buf_offset,
e->encoder_buf_sz,
&h,
sizeof(h));
e->encoder_buf_offset += nbytes;
return nbytes;
}
static void vidtv_s302m_write_frames(struct vidtv_encoder *e)
{
struct vidtv_access_unit *au = e->access_units;
struct vidtv_s302m_ctx *ctx = e->ctx;
u32 nbytes_per_unit = 0;
u32 nbytes = 0;
u32 au_sz = 0;
u16 sample;
u32 j;
while (au) {
au_sz = au->num_samples *
sizeof(struct vidtv_s302m_frame_16);
nbytes_per_unit = vidtv_s302m_write_h(e, au_sz);
for (j = 0; j < au->num_samples; ++j) {
sample = vidtv_s302m_get_sample(e);
nbytes_per_unit += vidtv_s302m_write_frame(e, sample);
if (e->src_buf)
e->src_buf_offset += sizeof(u16);
e->sample_count++;
}
au->nbytes = nbytes_per_unit;
if (au_sz + sizeof(struct vidtv_smpte_s302m_es) != nbytes_per_unit) {
pr_warn_ratelimited("write size was %u, expected %zu\n",
nbytes_per_unit,
au_sz + sizeof(struct vidtv_smpte_s302m_es));
}
nbytes += nbytes_per_unit;
au->offset = nbytes - nbytes_per_unit;
nbytes_per_unit = 0;
ctx->au_count++;
au = au->next;
}
}
static void *vidtv_s302m_encode(struct vidtv_encoder *e)
{
struct vidtv_s302m_ctx *ctx = e->ctx;
/*
* According to SMPTE 302M, an audio access unit is specified as those
* AES3 words that are associated with a corresponding video frame.
* Therefore, there is one audio access unit for every video access unit
* in the corresponding video encoder ('sync'), using the same values
* for PTS as used by the video encoder.
*
* Assuming that it is also possible to send audio without any
* associated video, as in a radio-like service, a single audio access unit
* is created with values for 'num_samples' and 'pts' taken empirically from
* ffmpeg
*/
vidtv_s302m_access_unit_destroy(e);
vidtv_s302m_alloc_au(e);
if (e->sync && e->sync->is_video_encoder) {
vidtv_s302m_compute_sample_count_from_video(e);
vidtv_s302m_compute_pts_from_video(e);
} else {
e->access_units->num_samples = FF_S302M_DEFAULT_NUM_FRAMES;
e->access_units->pts = (ctx->au_count * FF_S302M_DEFAULT_PTS_INCREMENT) +
FF_S302M_DEFAULT_PTS_OFFSET;
}
vidtv_s302m_write_frames(e);
return e->encoder_buf;
}
static u32 vidtv_s302m_clear(struct vidtv_encoder *e)
{
struct vidtv_access_unit *au = e->access_units;
u32 count = 0;
while (au) {
count++;
au = au->next;
}
vidtv_s302m_access_unit_destroy(e);
memset(e->encoder_buf, 0, VIDTV_S302M_BUF_SZ);
e->encoder_buf_offset = 0;
return count;
}
struct vidtv_encoder
*vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args)
{
u32 priv_sz = sizeof(struct vidtv_s302m_ctx);
struct vidtv_s302m_ctx *ctx;
struct vidtv_encoder *e;
e = kzalloc(sizeof(*e), GFP_KERNEL);
if (!e)
return NULL;
e->id = S302M;
if (args.name)
e->name = kstrdup(args.name, GFP_KERNEL);
e->encoder_buf = vzalloc(VIDTV_S302M_BUF_SZ);
e->encoder_buf_sz = VIDTV_S302M_BUF_SZ;
e->encoder_buf_offset = 0;
e->sample_count = 0;
e->src_buf = (args.src_buf) ? args.src_buf : NULL;
e->src_buf_sz = (args.src_buf) ? args.src_buf_sz : 0;
e->src_buf_offset = 0;
e->is_video_encoder = false;
ctx = kzalloc(priv_sz, GFP_KERNEL);
if (!ctx) {
kfree(e);
return NULL;
}
e->ctx = ctx;
ctx->last_duration = 0;
e->encode = vidtv_s302m_encode;
e->clear = vidtv_s302m_clear;
e->es_pid = cpu_to_be16(args.es_pid);
e->stream_id = cpu_to_be16(PES_PRIVATE_STREAM_1);
e->sync = args.sync;
e->sampling_rate_hz = S302M_SAMPLING_RATE_HZ;
e->last_sample_cb = args.last_sample_cb;
e->destroy = vidtv_s302m_encoder_destroy;
if (args.head) {
while (args.head->next)
args.head = args.head->next;
args.head->next = e;
}
e->next = NULL;
return e;
}
void vidtv_s302m_encoder_destroy(struct vidtv_encoder *e)
{
if (e->id != S302M) {
pr_err_ratelimited("Encoder type mismatch, skipping.\n");
return;
}
vidtv_s302m_access_unit_destroy(e);
kfree(e->name);
vfree(e->encoder_buf);
kfree(e->ctx);
kfree(e);
}