mpv/audio/format.c

234 lines
7.1 KiB
C

/*
* Copyright (C) 2005 Alex Beregszaszi
*
* This file is part of mpv.
*
* mpv is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* mpv is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with mpv. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>
#include <limits.h>
#include <assert.h>
#include "common/common.h"
#include "audio/filter/af.h"
int af_fmt2bps(int format)
{
switch (format & AF_FORMAT_BITS_MASK) {
case AF_FORMAT_8BIT: return 1;
case AF_FORMAT_16BIT: return 2;
case AF_FORMAT_24BIT: return 3;
case AF_FORMAT_32BIT: return 4;
case AF_FORMAT_64BIT: return 8;
}
return 0;
}
int af_fmt2bits(int format)
{
return af_fmt2bps(format) * 8;
}
static int bits_to_mask(int bits)
{
switch (bits) {
case 8: return AF_FORMAT_8BIT;
case 16: return AF_FORMAT_16BIT;
case 24: return AF_FORMAT_24BIT;
case 32: return AF_FORMAT_32BIT;
case 64: return AF_FORMAT_64BIT;
}
return 0;
}
int af_fmt_change_bits(int format, int bits)
{
if (!af_fmt_is_valid(format))
return 0;
int mask = bits_to_mask(bits);
format = (format & ~AF_FORMAT_BITS_MASK) | mask;
return af_fmt_is_valid(format) ? format : 0;
}
static const int planar_formats[][2] = {
{AF_FORMAT_U8P, AF_FORMAT_U8},
{AF_FORMAT_S16P, AF_FORMAT_S16},
{AF_FORMAT_S32P, AF_FORMAT_S32},
{AF_FORMAT_FLOATP, AF_FORMAT_FLOAT},
{AF_FORMAT_DOUBLEP, AF_FORMAT_DOUBLE},
};
// Return the planar format corresponding to the given format.
// If the format is already planar, return it.
// Return 0 if there's no equivalent.
int af_fmt_to_planar(int format)
{
for (int n = 0; n < MP_ARRAY_SIZE(planar_formats); n++) {
if (planar_formats[n][1] == format)
return planar_formats[n][0];
if (planar_formats[n][0] == format)
return format;
}
return 0;
}
// Return the interleaved format corresponding to the given format.
// If the format is already interleaved, return it.
// Always succeeds if format is actually planar; otherwise return 0.
int af_fmt_from_planar(int format)
{
for (int n = 0; n < MP_ARRAY_SIZE(planar_formats); n++) {
if (planar_formats[n][0] == format)
return planar_formats[n][1];
}
return format;
}
const struct af_fmt_entry af_fmtstr_table[] = {
{"u8", AF_FORMAT_U8},
{"s8", AF_FORMAT_S8},
{"u16", AF_FORMAT_U16},
{"s16", AF_FORMAT_S16},
{"u24", AF_FORMAT_U24},
{"s24", AF_FORMAT_S24},
{"u32", AF_FORMAT_U32},
{"s32", AF_FORMAT_S32},
{"float", AF_FORMAT_FLOAT},
{"double", AF_FORMAT_DOUBLE},
{"u8p", AF_FORMAT_U8P},
{"s16p", AF_FORMAT_S16P},
{"s32p", AF_FORMAT_S32P},
{"floatp", AF_FORMAT_FLOATP},
{"doublep", AF_FORMAT_DOUBLEP},
{"spdif-aac", AF_FORMAT_S_AAC},
{"spdif-ac3", AF_FORMAT_S_AC3},
{"spdif-dts", AF_FORMAT_S_DTS},
{"spdif-dtshd", AF_FORMAT_S_DTSHD},
{"spdif-eac3", AF_FORMAT_S_EAC3},
{"spdif-mp3", AF_FORMAT_S_MP3},
{"spdif-truehd",AF_FORMAT_S_TRUEHD},
{0}
};
bool af_fmt_is_valid(int format)
{
for (int i = 0; af_fmtstr_table[i].name; i++) {
if (af_fmtstr_table[i].format == format)
return true;
}
return false;
}
const char *af_fmt_to_str(int format)
{
for (int i = 0; af_fmtstr_table[i].name; i++) {
if (af_fmtstr_table[i].format == format)
return af_fmtstr_table[i].name;
}
return "??";
}
int af_fmt_seconds_to_bytes(int format, float seconds, int channels, int samplerate)
{
assert(!AF_FORMAT_IS_PLANAR(format));
int bps = af_fmt2bps(format);
int framelen = channels * bps;
int bytes = seconds * bps * samplerate;
if (bytes % framelen)
bytes += framelen - (bytes % framelen);
return bytes;
}
int af_str2fmt_short(bstr str)
{
for (int i = 0; af_fmtstr_table[i].name; i++) {
if (!bstrcasecmp0(str, af_fmtstr_table[i].name))
return af_fmtstr_table[i].format;
}
return 0;
}
void af_fill_silence(void *dst, size_t bytes, int format)
{
bool us = (format & AF_FORMAT_SIGN_MASK) == AF_FORMAT_US;
memset(dst, us ? 0x80 : 0, bytes);
}
#define FMT_DIFF(type, a, b) (((a) & type) - ((b) & type))
// Returns a "score" that serves as heuristic how lossy or hard a conversion is.
// If the formats are equal, 1024 is returned. If they are gravely incompatible
// (like s16<->ac3), INT_MIN is returned. If there is implied loss of precision
// (like s16->s8), a value <0 is returned.
int af_format_conversion_score(int dst_format, int src_format)
{
if (dst_format == AF_FORMAT_UNKNOWN || src_format == AF_FORMAT_UNKNOWN)
return INT_MIN;
if (dst_format == src_format)
return 1024;
// Can't be normally converted
if (AF_FORMAT_IS_SPECIAL(dst_format) || AF_FORMAT_IS_SPECIAL(src_format))
return INT_MIN;
int score = 1024;
if (FMT_DIFF(AF_FORMAT_INTERLEAVING_MASK, dst_format, src_format))
score -= 1; // has to (de-)planarize
if (FMT_DIFF(AF_FORMAT_SIGN_MASK, dst_format, src_format))
score -= 4; // has to swap sign
if (FMT_DIFF(AF_FORMAT_TYPE_MASK, dst_format, src_format)) {
int dst_bits = dst_format & AF_FORMAT_BITS_MASK;
if ((dst_format & AF_FORMAT_TYPE_MASK) == AF_FORMAT_F) {
// For int->float, always prefer 32 bit float.
score -= dst_bits == AF_FORMAT_32BIT ? 8 : 0;
} else {
// For float->int, always prefer highest bit depth int
score -= 8 * (AF_FORMAT_64BIT - dst_bits);
}
} else {
int bits = FMT_DIFF(AF_FORMAT_BITS_MASK, dst_format, src_format);
if (bits > 0) {
score -= 8 * bits; // has to add padding
} else if (bits < 0) {
score -= 1024 - 8 * bits; // has to reduce bit depth
}
}
// Consider this the worst case.
if (FMT_DIFF(AF_FORMAT_TYPE_MASK, dst_format, src_format))
score -= 2048; // has to convert float<->int
return score;
}
// Return the number of samples that make up one frame in this format.
// You get the byte size by multiplying them with sample size and channel count.
int af_format_sample_alignment(int format)
{
switch (format) {
case AF_FORMAT_S_AAC: return 16384 / 4;
case AF_FORMAT_S_AC3: return 6144 / 4;
case AF_FORMAT_S_DTSHD: return 32768 / 16;
case AF_FORMAT_S_DTS: return 2048 / 4;
case AF_FORMAT_S_EAC3: return 24576 / 4;
case AF_FORMAT_S_MP3: return 4608 / 4;
case AF_FORMAT_S_TRUEHD: return 61440 / 16;
default: return 1;
}
}