pipewire/spa/plugins/audioconvert/fmt-ops.c

/* Spa
 * Copyright (C) 2018 Wim Taymans <wim.taymans@gmail.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#include <string.h>
#include <stdio.h>

#include <spa/utils/defs.h>

#define U8_MIN		0
#define U8_MAX		255
#define U8_SCALE	127
#define U8_OFFS		128

#define S16_MIN		-32767
#define S16_MAX		32767
#define S16_SCALE	32767

#define S24_MIN		-8388607
#define S24_MAX		8388607
#define S24_MAX_F	8388607.0f
#define S24_SCALE	8388607

#define S32_MIN		-2147483647
#define S32_MAX		2147483647
#define S32_SCALE	2147483647

#if defined (__SSE__)
#include "fmt-ops-sse.c"
#endif

static void
conv_copy(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i;
	for (i = 0; i < n_src; i++)
		memcpy(dst[i], src[i], n_bytes);
}

#define U8_TO_F32(v)	(((v) * (1.0f / U8_OFFS)) - 1.0)

static void
conv_u8_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	for (i = 0; i < n_src; i++) {
		const uint8_t *s = src[i];
		float *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = U8_TO_F32(s[j]);
	}
}

static void
conv_u8_to_f32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint8_t *s = src[0];
	float **d = (float **) dst;
	int i, j;

	n_bytes /= n_dst;
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = U8_TO_F32(*s++);
	}
}

static void
conv_u8d_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint8_t **s = (const uint8_t **) src;
	float *d = dst[0];
	int i, j;

	n_bytes /= n_src;
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_src; i++)
			*d++ = U8_TO_F32(s[i][j]);
	}
}

#define S16_TO_F32(v)	((v) * (1.0f / S16_SCALE))

static void
conv_s16_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(int16_t);
	for (i = 0; i < n_src; i++) {
		const int16_t *s = src[i];
		float *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = S16_TO_F32(s[j]);
	}
}

static void
conv_s16_to_f32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int16_t *s = src[0];
	float **d = (float **) dst;
	int i, j;

	n_bytes /= (sizeof(int16_t) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = S16_TO_F32(*s++);
	}
}

static void
conv_s16d_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int16_t **s = (const int16_t **) src;
	float *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(int16_t);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = S16_TO_F32(s[i][n]);
	}
}

#define S32_TO_F32(v)	((v) * (1.0f / S32_SCALE))

static void
conv_s32_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(int32_t);
	for (i = 0; i < n_src; i++) {
		const int32_t *s = src[i];
		float *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = S32_TO_F32(s[j]);
	}
}

static void
conv_s32_to_f32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int32_t *s = src[0];
	float **d = (float **) dst;
	int i, j;

	n_bytes /= (sizeof(int32_t) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = S32_TO_F32(*s++);
	}
}

static void
conv_s32d_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int32_t **s = (const int32_t **) src;
	float *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(int32_t);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = S32_TO_F32(s[i][n]);
	}
}

#define READ24(s) (((uint32_t)s[0] << 16) | ((uint32_t)s[1] << 8) | ((uint32_t)s[2]))

#define S24_TO_F32(v)	((((int32_t)v)<<8) * (1.0f / S32_SCALE))

static void
conv_s24_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= 3;
	for (i = 0; i < n_src; i++) {
		const int8_t *s = src[i];
		float *d = dst[i];

		for (j = 0; j < n_bytes; j++) {
			d[j] = S24_TO_F32(READ24(s));
			s += 3;
		}
	}
}

static void
conv_s24_to_f32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint8_t *s = src[0];
	float **d = (float **) dst;
	int i, j;

	n_bytes /= (3 * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++) {
			d[i][j] = S24_TO_F32(READ24(s));
			s += 3;
		}
	}
}

static void
conv_s24d_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint8_t **s = (const uint8_t **) src;
	float *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / 3;
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++) {
			*d++ = S24_TO_F32(READ24(s[i]));
			s += 3;
		}
	}
}

static void
conv_s24_32_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(int32_t);
	for (i = 0; i < n_src; i++) {
		const int32_t *s = src[i];
		float *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = S24_TO_F32(s[j]);
	}
}

static void
conv_s24_32_to_f32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int32_t *s = src[0];
	float **d = (float **) dst;
	int i, j;

	n_bytes /= (sizeof(int32_t) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = S24_TO_F32(*s++);
	}
}

static void
conv_s24_32d_to_f32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int32_t **s = (const int32_t **) src;
	float *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(int32_t);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = S24_TO_F32(s[i][n]);
	}
}

#define F32_TO_U8(v)			\
({					\
	typeof(v) _v = (v);		\
	_v < -1.0f ? U8_MIN :		\
	_v >= 1.0f ? U8_MAX :		\
	(_v * U8_SCALE) + U8_OFFS;	\
})

static void
conv_f32_to_u8(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(float);
	for (i = 0; i < n_src; i++) {
		const float *s = src[i];
		int8_t *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = F32_TO_U8(s[j]);
	}
}

static void
conv_f32_to_u8d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float *s = src[0];
	int8_t **d = (int8_t **) dst;
	int i, j;

	n_bytes /= (sizeof(float) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = F32_TO_U8(*s++);
	}
}

static void
conv_f32d_to_u8(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float **s = (const float **) src;
	int8_t *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(float);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = F32_TO_U8(s[i][n]);
	}
}

#define F32_TO_S16(v)		\
({				\
	typeof(v) _v = (v);	\
	_v < -1.0f ? S16_MIN :	\
	_v >= 1.0f ? S16_MAX :	\
	_v * S16_SCALE;		\
})

static void
conv_f32_to_s16(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(float);
	for (i = 0; i < n_src; i++) {
		const float *s = src[i];
		int16_t *d = dst[i];

		for (n = 0; n < n_samples; n++)
			d[n] = F32_TO_S16(s[n]);
	}
}

static void
conv_f32_to_s16d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float *s = src[0];
	int16_t **d = (int16_t **) dst;
	int i, n, n_samples;

	n_samples = n_bytes / (sizeof(float) * n_dst);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_dst; i++)
			d[i][n] = F32_TO_S16(*s++);
	}
}

static void
conv_f32d_to_s16(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float **s = (const float **) src;
	int16_t *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(float);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = F32_TO_S16(s[i][n]);
	}
}

#define F32_TO_S32(v)		\
({				\
	typeof(v) _v = (v);	\
	_v < -1.0f ? S32_MIN :	\
	_v >= 1.0f ? S32_MAX :	\
	_v * S32_SCALE;		\
})

static void
conv_f32_to_s32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(float);
	for (i = 0; i < n_src; i++) {
		const float *s = src[i];
		int32_t *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = F32_TO_S32(s[j]);
	}
}

static void
conv_f32_to_s32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float *s = src[0];
	int32_t **d = (int32_t **) dst;
	int i, j;

	n_bytes /= (sizeof(float) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = F32_TO_S32(*s++);
	}
}

static void
conv_f32d_to_s32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float **s = (const float **) src;
	int32_t *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(float);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = F32_TO_S32(s[i][n]);
	}
}


#define F32_TO_S24(v)			\
({					\
	typeof(v) _v = (v);		\
	_v < -1.0f ? S24_MIN :		\
	_v >= 1.0f ? S24_MAX :		\
	(uint32_t) (_v * S24_SCALE);	\
})

#define WRITE24(d,v)			\
({					\
	typeof(v) _v = (v);		\
	d[0] = (uint8_t) (_v >> 16);	\
	d[1] = (uint8_t) (_v >> 8);	\
	d[2] = (uint8_t) _v;		\
})

static void
conv_f32_to_s24(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(float);
	for (i = 0; i < n_src; i++) {
		const float *s = src[i];
		int8_t *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			WRITE24(d, F32_TO_S24(s[j]));
			d += 3;
	}
}

static void
conv_f32_to_s24d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float *s = src[0];
	int8_t **d = (int8_t **) dst;
	int i, j;

	n_bytes /= (sizeof(float) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++) {
			WRITE24(d[i], F32_TO_S24(*s++));
			d[i] += 3;
		}
	}
}

static void
conv_f32d_to_s24(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float **s = (const float **) src;
	int8_t *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(float);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++) {
			WRITE24(d, F32_TO_S24(s[i][n]));
			d += 3;
		}
	}
}


static void
conv_f32_to_s24_32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	int i, j;

	n_bytes /= sizeof(float);
	for (i = 0; i < n_src; i++) {
		const float *s = src[i];
		int32_t *d = dst[i];

		for (j = 0; j < n_bytes; j++)
			d[j] = F32_TO_S24(s[j]);
	}
}

static void
conv_f32_to_s24_32d(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float *s = src[0];
	int32_t **d = (int32_t **) dst;
	int i, j;

	n_bytes /= (sizeof(float) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = F32_TO_S24(*s++);
	}
}

static void
conv_f32d_to_s24_32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const float **s = (const float **) src;
	int32_t *d = dst[0];
	int i, n, n_samples;

	n_samples = n_bytes / sizeof(float);
	for (n = 0; n < n_samples; n++) {
		for (i = 0; i < n_src; i++)
			*d++ = F32_TO_S24(s[i][n]);
	}
}

static void
deinterleave_8(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint8_t *s = src[0];
	uint8_t **d = (uint8_t **) dst;
	int i, j;

	n_bytes /= (sizeof(uint8_t) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = *s++;
	}
}

static void
deinterleave_16(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint16_t *s = src[0];
	uint16_t **d = (uint16_t **) dst;
	int i, j;

	n_bytes /= (sizeof(uint16_t) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = *s++;
	}
}

static void
deinterleave_24(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint8_t *s = src[0];
	uint8_t **d = (uint8_t **) dst;
	int i, j;

	n_bytes /= (3 * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++) {
			WRITE24(d[i], READ24(s));
			d += 3;
			s += 3;
		}
	}
}

static void
deinterleave_32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const uint32_t *s = src[0];
	uint32_t **d = (uint32_t **) dst;
	int i, j;

	n_bytes /= (sizeof(uint32_t) * n_dst);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_dst; i++)
			d[i][j] = *s++;
	}
}

static void
interleave_8(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int8_t **s = (const int8_t **) src;
	uint8_t *d = dst[0];
	int i, j;

	n_bytes /= sizeof(uint8_t);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_src; i++)
			*d++ = s[i][j];
	}
}

static void
interleave_16(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int16_t **s = (const int16_t **) src;
	uint16_t *d = dst[0];
	int i, j;

	n_bytes /= sizeof(uint16_t);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_src; i++)
			*d++ = s[i][j];
	}
}

static void
interleave_24(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int8_t **s = (const int8_t **) src;
	uint8_t *d = dst[0];
	int i, j;

	n_bytes /= 3;
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_src; i++) {
			WRITE24(d, READ24(s[i]));
			d += 3;
			s += 3;
		}
	}
}

static void
interleave_32(void *data, int n_dst, void *dst[n_dst], int n_src, const void *src[n_src], int n_bytes)
{
	const int32_t **s = (const int32_t **) src;
	uint32_t *d = dst[0];
	int i, j;

	n_bytes /= sizeof(uint32_t);
	for (j = 0; j < n_bytes; j++) {
		for (i = 0; i < n_src; i++)
			*d++ = s[i][j];
	}
}

typedef void (*convert_func_t) (void *data, int n_dst, void *dst[n_dst],
				int n_src, const void *src[n_src], int n_bytes);

static const struct conv_info {
	off_t src_fmt;
	off_t dst_fmt;
#define FEATURE_SSE	(1<<0)
	uint32_t features;

	convert_func_t i2i;
	convert_func_t i2d;
	convert_func_t d2i;
} conv_table[] =
{
	/* to f32 */
	{ offsetof(struct spa_type_audio_format, U8),
	  offsetof(struct spa_type_audio_format, F32), 0,
		conv_u8_to_f32, conv_u8_to_f32d, conv_u8d_to_f32 },
#if defined (__SSE2__)
	{ offsetof(struct spa_type_audio_format, S16),
	  offsetof(struct spa_type_audio_format, F32), FEATURE_SSE,
		conv_s16_to_f32, conv_s16_to_f32d_sse, conv_s16d_to_f32 },
#endif
	{ offsetof(struct spa_type_audio_format, S16),
	  offsetof(struct spa_type_audio_format, F32), 0,
		conv_s16_to_f32, conv_s16_to_f32d, conv_s16d_to_f32 },
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, F32), 0,
		conv_copy, deinterleave_32, interleave_32 },
	{ offsetof(struct spa_type_audio_format, S32),
	  offsetof(struct spa_type_audio_format, F32), 0,
		conv_s32_to_f32, conv_s32_to_f32d, conv_s32d_to_f32 },
	{ offsetof(struct spa_type_audio_format, S24),
	  offsetof(struct spa_type_audio_format, F32), 0,
		conv_s24_to_f32, conv_s24_to_f32d, conv_s24d_to_f32 },
	{ offsetof(struct spa_type_audio_format, S24_32),
	  offsetof(struct spa_type_audio_format, F32), 0,
		conv_s24_32_to_f32, conv_s24_32_to_f32d, conv_s24_32d_to_f32 },

	/* from f32 */
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, U8), 0,
		conv_f32_to_u8, conv_f32_to_u8d, conv_f32d_to_u8 },
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, S16), 0,
		conv_f32_to_s16, conv_f32_to_s16d, conv_f32d_to_s16 },
#if defined (__SSE2__)
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, S32), FEATURE_SSE,
		conv_f32_to_s32, conv_f32_to_s32d, conv_f32d_to_s32_sse },
#endif
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, S32), 0,
		conv_f32_to_s32, conv_f32_to_s32d, conv_f32d_to_s32 },
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, S24), 0,
		conv_f32_to_s24, conv_f32_to_s24d, conv_f32d_to_s24 },
	{ offsetof(struct spa_type_audio_format, F32),
	  offsetof(struct spa_type_audio_format, S24_32), 0,
		conv_f32_to_s24_32, conv_f32_to_s24_32d, conv_f32d_to_s24_32 },

	/* u8 */
	{ offsetof(struct spa_type_audio_format, U8),
	  offsetof(struct spa_type_audio_format, U8), 0,
		conv_copy, deinterleave_8, interleave_8 },

	/* s16 */
	{ offsetof(struct spa_type_audio_format, S16),
	  offsetof(struct spa_type_audio_format, S16), 0,
		conv_copy, deinterleave_16, interleave_16 },

	/* s32 */
	{ offsetof(struct spa_type_audio_format, S32),
	  offsetof(struct spa_type_audio_format, S32), 0,
		conv_copy, deinterleave_32, interleave_32 },

	/* s24 */
	{ offsetof(struct spa_type_audio_format, S24),
	  offsetof(struct spa_type_audio_format, S24), 0,
		conv_copy, deinterleave_24, interleave_24 },

	/* s24_32 */
	{ offsetof(struct spa_type_audio_format, S24_32),
	  offsetof(struct spa_type_audio_format, S24_32), 0,
		conv_copy, deinterleave_32, interleave_32 },
};

static const struct conv_info *find_conv_info(struct spa_type_audio_format *audio_format,
		uint32_t src_fmt, uint32_t dst_fmt, uint32_t features)
{
	int i;

	for (i = 0; i < SPA_N_ELEMENTS(conv_table); i++) {
		if (*SPA_MEMBER(audio_format, conv_table[i].src_fmt, uint32_t) == src_fmt &&
		    *SPA_MEMBER(audio_format, conv_table[i].dst_fmt, uint32_t) == dst_fmt &&
		    (conv_table[i].features == 0 || (conv_table[i].features & features) != 0))
			return &conv_table[i];
	}
	return NULL;
}