xconvert.c

xmms-1.2.10.tar.gz学习使用的就下吧

/*
 *  Copyright (C) 2001-2003  Haavard Kvaalen <[e-mail]>
 *
 *  Licensed under GNU LGPL version 2.
 */

#include "config.h"
#include <stdlib.h>
#include <xmms/plugin.h>
#include "xconvert.h"

#ifdef WORDS_BIGENDIAN
# define IS_BIG_ENDIAN TRUE
#else
# define IS_BIG_ENDIAN FALSE
#endif

struct buffer {
	void *buffer;
	int size;
};

struct xmms_convert_buffers {
	struct buffer format_buffer, stereo_buffer, freq_buffer;
};

struct xmms_convert_buffers* xmms_convert_buffers_new(void)
{
	return g_malloc0(sizeof(struct xmms_convert_buffers));
}
	
static void* convert_get_buffer(struct buffer *buffer, size_t size)
{
	if (size > 0 && size <= buffer->size)
		return buffer->buffer;

	buffer->size = size;
	buffer->buffer = g_realloc(buffer->buffer, size);
	return buffer->buffer;
}

void xmms_convert_buffers_free(struct xmms_convert_buffers* buf)
{
	convert_get_buffer(&buf->format_buffer, 0);
	convert_get_buffer(&buf->stereo_buffer, 0);
	convert_get_buffer(&buf->freq_buffer, 0);
}

void xmms_convert_buffers_destroy(struct xmms_convert_buffers* buf)
{
	if (!buf)
		return;
	xmms_convert_buffers_free(buf);
	g_free(buf);
}

static int convert_swap_endian(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint16 *ptr = *data;
	int i;
	for (i = 0; i < length; i += 2, ptr++)
		*ptr = GUINT16_SWAP_LE_BE(*ptr);

	return i;
}

static int convert_swap_sign_and_endian_to_native(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint16 *ptr = *data;
	int i;
	for (i = 0; i < length; i += 2, ptr++)
		*ptr = GUINT16_SWAP_LE_BE(*ptr) ^ 1 << 15;

	return i;
}

static int convert_swap_sign_and_endian_to_alien(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint16 *ptr = *data;
	int i;
	for (i = 0; i < length; i += 2, ptr++)
		*ptr = GUINT16_SWAP_LE_BE(*ptr ^ 1 << 15);

	return i;
}

static int convert_swap_sign16(struct xmms_convert_buffers* buf, void **data, int length)
{
	gint16 *ptr = *data;
	int i;
	for (i = 0; i < length; i += 2, ptr++)
		*ptr ^= 1 << 15;

	return i;
}

static int convert_swap_sign8(struct xmms_convert_buffers* buf, void **data, int length)
{
	gint8 *ptr = *data;
	int i;
	for (i = 0; i < length; i++)
		*ptr++ ^= 1 << 7;

	return i;
}

static int convert_to_8_native_endian(struct xmms_convert_buffers* buf, void **data, int length)
{
	gint8 *output = *data;
	gint16 *input = *data;
	int i;
	for (i = 0; i < length / 2; i++)
		*output++ = *input++ >> 8;

	return i;
}

static int convert_to_8_native_endian_swap_sign(struct xmms_convert_buffers* buf, void **data, int length)
{
	gint8 *output = *data;
	gint16 *input = *data;
	int i;
	for (i = 0; i < length / 2; i++)
		*output++ = (*input++ >> 8) ^ (1 << 7);

	return i;
}


static int convert_to_8_alien_endian(struct xmms_convert_buffers* buf, void **data, int length)
{
	gint8 *output = *data;
	gint16 *input = *data;
	int i;
	for (i = 0; i < length / 2; i++)
		*output++ = *input++ & 0xff;

	return i;
}

static int convert_to_8_alien_endian_swap_sign(struct xmms_convert_buffers* buf, void **data, int length)
{
	gint8 *output = *data;
	gint16 *input = *data;
	int i;
	for (i = 0; i < length / 2; i++)
		*output++ = (*input++ & 0xff) ^ (1 << 7);

	return i;
}

static int convert_to_16_native_endian(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint8 *input = *data;
	guint16 *output;
	int i;
	*data = convert_get_buffer(&buf->format_buffer, length * 2);
	output = *data;
	for (i = 0; i < length; i++)
		*output++ = *input++ << 8;

	return i * 2;
}

static int convert_to_16_native_endian_swap_sign(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint8 *input = *data;
	guint16 *output;
	int i;
	*data = convert_get_buffer(&buf->format_buffer, length * 2);
	output = *data;
	for (i = 0; i < length; i++)
		*output++ = (*input++ << 8) ^ (1 << 15);

	return i * 2;
}


static int convert_to_16_alien_endian(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint8 *input = *data;
	guint16 *output;
	int i;
	*data = convert_get_buffer(&buf->format_buffer, length * 2);
	output = *data;
	for (i = 0; i < length; i++)
		*output++ = *input++;

	return i * 2;
}

static int convert_to_16_alien_endian_swap_sign(struct xmms_convert_buffers* buf, void **data, int length)
{
	guint8 *input = *data;
	guint16 *output;
	int i;
	*data = convert_get_buffer(&buf->format_buffer, length * 2);
	output = *data;
	for (i = 0; i < length; i++)
		*output++ = *input++ ^ (1 << 7);

	return i * 2;
}

static AFormat unnativize(AFormat fmt)
{
	if (fmt == FMT_S16_NE)
	{
		if (IS_BIG_ENDIAN)
			return FMT_S16_BE;
		else
			return FMT_S16_LE;
	}
	if (fmt == FMT_U16_NE)
	{
		if (IS_BIG_ENDIAN)
			return FMT_U16_BE;
		else
			return FMT_U16_LE;
	}
	return fmt;
}

convert_func_t xmms_convert_get_func(AFormat output, AFormat input)
{
	output = unnativize(output);
	input = unnativize(input);

	if (output == input)
		return NULL;

	if ((output == FMT_U16_BE && input == FMT_U16_LE) ||
	    (output == FMT_U16_LE && input == FMT_U16_BE) ||
	    (output == FMT_S16_BE && input == FMT_S16_LE) ||
	    (output == FMT_S16_LE && input == FMT_S16_BE))
		return convert_swap_endian;

	if ((output == FMT_U16_BE && input == FMT_S16_BE) ||
	    (output == FMT_U16_LE && input == FMT_S16_LE) ||
	    (output == FMT_S16_BE && input == FMT_U16_BE) ||
	    (output == FMT_S16_LE && input == FMT_U16_LE))
		return convert_swap_sign16;

	if ((IS_BIG_ENDIAN &&
	     ((output == FMT_U16_BE && input == FMT_S16_LE) ||
	      (output == FMT_S16_BE && input == FMT_U16_LE))) ||
	    (!IS_BIG_ENDIAN &&
	     ((output == FMT_U16_LE && input == FMT_S16_BE) ||
	      (output == FMT_S16_LE && input == FMT_U16_BE))))
		return convert_swap_sign_and_endian_to_native;
		
	if ((!IS_BIG_ENDIAN &&
	     ((output == FMT_U16_BE && input == FMT_S16_LE) ||
	      (output == FMT_S16_BE && input == FMT_U16_LE))) ||
	    (IS_BIG_ENDIAN &&
	     ((output == FMT_U16_LE && input == FMT_S16_BE) ||
	      (output == FMT_S16_LE && input == FMT_U16_BE))))
		return convert_swap_sign_and_endian_to_alien;

	if ((IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_U16_BE) ||
	      (output == FMT_S8 && input == FMT_S16_BE))) ||
	    (!IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_U16_LE) ||
	      (output == FMT_S8 && input == FMT_S16_LE))))
		return convert_to_8_native_endian;

	if ((IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_S16_BE) ||
	      (output == FMT_S8 && input == FMT_U16_BE))) ||
	    (!IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_S16_LE) ||
	      (output == FMT_S8 && input == FMT_U16_LE))))
		return convert_to_8_native_endian_swap_sign;

	if ((!IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_U16_BE) ||
	      (output == FMT_S8 && input == FMT_S16_BE))) ||
	    (IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_U16_LE) ||
	      (output == FMT_S8 && input == FMT_S16_LE))))
		return convert_to_8_alien_endian;

	if ((!IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_S16_BE) ||
	      (output == FMT_S8 && input == FMT_U16_BE))) ||
	    (IS_BIG_ENDIAN &&
	     ((output == FMT_U8 && input == FMT_S16_LE) ||
	      (output == FMT_S8 && input == FMT_U16_LE))))
		return convert_to_8_alien_endian_swap_sign;

	if ((output == FMT_U8 && input == FMT_S8) ||
	    (output == FMT_S8 && input == FMT_U8))
		return convert_swap_sign8;

	if ((IS_BIG_ENDIAN &&
	     ((output == FMT_U16_BE && input == FMT_U8) ||
	      (output == FMT_S16_BE && input == FMT_S8))) ||
	    (!IS_BIG_ENDIAN &&
	     ((output == FMT_U16_LE && input == FMT_U8) ||
	      (output == FMT_S16_LE && input == FMT_S8))))
		return convert_to_16_native_endian;

	if ((IS_BIG_ENDIAN &&
	     ((output == FMT_U16_BE && input == FMT_S8) ||
	      (output == FMT_S16_BE && input == FMT_U8))) ||
	    (!IS_BIG_ENDIAN &&
	     ((output == FMT_U16_LE && input == FMT_S8) ||
	      (output == FMT_S16_LE && input == FMT_U8))))
		return convert_to_16_native_endian_swap_sign;

	if ((!IS_BIG_ENDIAN &&
	     ((output == FMT_U16_BE && input == FMT_U8) ||
	      (output == FMT_S16_BE && input == FMT_S8))) ||
	    (IS_BIG_ENDIAN &&
	     ((output == FMT_U16_LE && input == FMT_U8) ||
	      (output == FMT_S16_LE && input == FMT_S8))))
		return convert_to_16_alien_endian;

	if ((!IS_BIG_ENDIAN &&
	     ((output == FMT_U16_BE && input == FMT_S8) ||
	      (output == FMT_S16_BE && input == FMT_U8))) ||
	    (IS_BIG_ENDIAN &&
	     ((output == FMT_U16_LE && input == FMT_S8) ||
	      (output == FMT_S16_LE && input == FMT_U8))))
		return convert_to_16_alien_endian_swap_sign;

	g_warning("Translation needed, but not available.\n"
		  "Input: %d; Output %d.", input, output);
	return NULL;
}

static int convert_mono_to_stereo(struct xmms_convert_buffers* buf, void **data, int length, int b16)
{
	int i;
	void *outbuf = convert_get_buffer(&buf->stereo_buffer, length * 2);

	if (b16)
	{
		guint16 *output = outbuf, *input = *data;
		for (i = 0; i < length / 2; i++)
		{
			*output++ = *input;
			*output++ = *input;
			input++;
		}
	}
	else 
	{
		guint8 *output = outbuf, *input = *data;
		for (i = 0; i < length; i++)
		{
			*output++ = *input;
			*output++ = *input;
			input++;
		}
	}
	*data = outbuf;

	return length * 2;
}

static int convert_mono_to_stereo_8(struct xmms_convert_buffers* buf, void **data, int length)
{
	return convert_mono_to_stereo(buf, data, length, FALSE);