--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/decoders/libmpg123/format.c	Fri Jan 30 02:44:47 2009 -0500
@@ -0,0 +1,321 @@
+/*
+	format:routines to deal with audio (output) format
+
+	copyright 2008 by the mpg123 project - free software under the terms of the LGPL 2.1
+	see COPYING and AUTHORS files in distribution or http://mpg123.org
+	initially written by Thomas Orgis, starting with parts of the old audio.c, with only faintly manage to show now
+*/
+
+#include "mpg123lib_intern.h"
+#include "debug.h"
+
+/* static int chans[NUM_CHANNELS] = { 1 , 2 }; */
+static const long my_rates[MPG123_RATES] = /* only the standard rates */
+{
+	 8000, 11025, 12000, 
+	16000, 22050, 24000,
+	32000, 44100, 48000,
+};
+static const int my_encodings[MPG123_ENCODINGS] =
+{
+	MPG123_ENC_SIGNED_16, 
+	MPG123_ENC_UNSIGNED_16,
+	MPG123_ENC_UNSIGNED_8,
+	MPG123_ENC_SIGNED_8,
+	MPG123_ENC_ULAW_8,
+	MPG123_ENC_ALAW_8,
+	MPG123_ENC_SIGNED_32,
+	MPG123_ENC_UNSIGNED_32,
+	MPG123_ENC_FLOAT_32,
+	MPG123_ENC_FLOAT_64
+};
+
+/* Check if encoding (mask) is a valid one in this build. */
+static int good_enc(int enc)
+{
+	if(!(enc & MPG123_ENC_ANY)) return FALSE;
+#ifdef FLOATOUT
+#ifdef REAL_IS_FLOAT /* we know only 32bit*/
+	if(enc != MPG123_ENC_FLOAT_32) return FALSE;
+#else
+	if(enc != MPG123_ENC_FLOAT_64) return FALSE;
+#endif
+#else
+	if(enc & MPG123_ENC_FLOAT) return FALSE;
+#endif
+	if(enc & MPG123_ENC_32) return FALSE; /* Not supported yet. */
+	if(enc == MPG123_ENC_UNSIGNED_16) return FALSE; /* Not supported yet... ever? */
+
+	return TRUE;
+}
+
+void attribute_align_arg mpg123_rates(const long **list, size_t *number)
+{
+	if(list   != NULL) *list   = my_rates;
+	if(number != NULL) *number = sizeof(my_rates)/sizeof(long);
+}
+
+/* Now that's a bit tricky... One build of the library knows only a subset of the encodings. */
+void attribute_align_arg mpg123_encodings(const int **list, size_t *number)
+{
+	size_t offset = 0;
+	size_t n = sizeof(my_encodings)/sizeof(int)-4; /* The last 4 are special. */
+#ifdef FLOATOUT /* Skip integer encodings. */
+	n = 1;
+#ifdef REAL_IS_FLOAT /* we know only 32bit*/
+	offset = 8; /* Only 32bit float */
+#else
+	offset = 9; /* Only 64bit float */
+#endif
+#endif /* There should be a branch for 32bit integer; but that's not anywhere now. */
+	if(list   != NULL) *list   = my_encodings+offset;
+	if(number != NULL) *number = n;
+}
+
+/*	char audio_caps[NUM_CHANNELS][MPG123_RATES+1][MPG123_ENCODINGS]; */
+
+static int rate2num(mpg123_pars *mp, long r)
+{
+	int i;
+	for(i=0;i<MPG123_RATES;i++) if(my_rates[i] == r) return i;
+	if(mp && mp->force_rate != 0 && mp->force_rate == r) return MPG123_RATES;
+
+	return -1;
+}
+
+static int enc2num(int encoding)
+{
+	int i;
+	for(i=0;i<MPG123_ENCODINGS;++i)
+	if(my_encodings[i] == encoding) return i;
+
+	return -1;
+}
+
+static int cap_fit(mpg123_handle *fr, struct audioformat *nf, int f0, int f2)
+{
+	int i;
+	int c  = nf->channels-1;
+	int rn = rate2num(&fr->p, nf->rate);
+	if(rn >= 0)	for(i=f0;i<f2;i++)
+	{
+		if(fr->p.audio_caps[c][rn][i])
+		{
+			nf->encoding = my_encodings[i];
+			return 1;
+		}
+	}
+	return 0;
+}
+
+static int freq_fit(mpg123_handle *fr, struct audioformat *nf, int f0, int f2)
+{
+	nf->rate = frame_freq(fr)>>fr->p.down_sample;
+	if(cap_fit(fr,nf,f0,f2)) return 1;
+	nf->rate>>=1;
+	if(cap_fit(fr,nf,f0,f2)) return 1;
+	nf->rate>>=1;
+	if(cap_fit(fr,nf,f0,f2)) return 1;
+	return 0;
+}
+
+/* match constraints against supported audio formats, store possible setup in frame
+  return: -1: error; 0: no format change; 1: format change */
+int frame_output_format(mpg123_handle *fr)
+{
+	struct audioformat nf;
+	int f0=0;
+	int f2=MPG123_ENCODINGS-4; /* Omit the 32bit and float encodings. */
+	mpg123_pars *p = &fr->p;
+	/* initialize new format, encoding comes later */
+	nf.channels = fr->stereo;
+
+#ifdef FLOATOUT /* Skip integer encodings. */
+#ifdef REAL_IS_FLOAT /* we know only 32bit*/
+	f0 = 8; /* Only 32bit float */
+#else
+	f0 = 9; /* Only 64bit float */
+#endif
+	f2 = f0+1; /* Only one encoding to try... */
+#else
+	if(p->flags & MPG123_FORCE_8BIT) f0 = 2; /* skip the 16bit encodings */
+#endif /* There should be a branch for 32bit integer; but that's not anywhere now. */
+
+	/* force stereo is stronger */
+	if(p->flags & MPG123_FORCE_MONO)   nf.channels = 1;
+	if(p->flags & MPG123_FORCE_STEREO) nf.channels = 2;
+
+	if(p->force_rate)
+	{
+		nf.rate = p->force_rate;
+		if(cap_fit(fr,&nf,f0,2)) goto end;            /* 16bit encodings */
+		if(cap_fit(fr,&nf,2,f2)) goto end; /*  8bit encodings */
+
+		/* try again with different stereoness */
+		if(nf.channels == 2 && !(p->flags & MPG123_FORCE_STEREO)) nf.channels = 1;
+		else if(nf.channels == 1 && !(p->flags & MPG123_FORCE_MONO)) nf.channels = 2;
+
+		if(cap_fit(fr,&nf,f0,2)) goto end;            /* 16bit encodings */
+		if(cap_fit(fr,&nf,2,f2)) goto end; /*  8bit encodings */
+
+		if(NOQUIET)
+		error3( "Unable to set up output format! Constraints: %s%s%liHz.",
+		        ( p->flags & MPG123_FORCE_STEREO ? "stereo, " :
+		          (p->flags & MPG123_FORCE_MONO ? "mono, " : "") ),
+		        (p->flags & MPG123_FORCE_8BIT ? "8bit, " : ""),
+		        p->force_rate );
+/*		if(NOQUIET && p->verbose <= 1) print_capabilities(fr); */
+
+		fr->err = MPG123_BAD_OUTFORMAT;
+		return -1;
+	}
+
+	if(freq_fit(fr, &nf, f0, 2)) goto end; /* try rates with 16bit */
+	if(freq_fit(fr, &nf,  2, f2)) goto end; /* ... 8bit */
+
+	/* try again with different stereoness */
+	if(nf.channels == 2 && !(p->flags & MPG123_FORCE_STEREO)) nf.channels = 1;
+	else if(nf.channels == 1 && !(p->flags & MPG123_FORCE_MONO)) nf.channels = 2;
+
+	if(freq_fit(fr, &nf, f0, 2)) goto end; /* try rates with 16bit */
+	if(freq_fit(fr, &nf,  2, f2)) goto end; /* ... 8bit */
+
+	/* Here is the _bad_ end. */
+	if(NOQUIET)
+	error5( "Unable to set up output format! Constraints: %s%s%li, %li or %liHz.",
+	        ( p->flags & MPG123_FORCE_STEREO ? "stereo, " :
+	          (p->flags & MPG123_FORCE_MONO ? "mono, "  : "") ),
+	        (p->flags & MPG123_FORCE_8BIT  ? "8bit, " : ""),
+	        frame_freq(fr),  frame_freq(fr)>>1, frame_freq(fr)>>2 );
+/*	if(NOQUIET && p->verbose <= 1) print_capabilities(fr); */
+
+	fr->err = MPG123_BAD_OUTFORMAT;
+	return -1;
+
+end: /* Here is the _good_ end. */
+	/* we had a successful match, now see if there's a change */
+	if(nf.rate == fr->af.rate && nf.channels == fr->af.channels && nf.encoding == fr->af.encoding)
+	{
+		debug("Old format!");
+		return 0; /* the same format as before */
+	}
+	else /* a new format */
+	{
+		debug("New format!");
+		fr->af.rate = nf.rate;
+		fr->af.channels = nf.channels;
+		fr->af.encoding = nf.encoding;
+		return 1;
+	}
+}
+
+int attribute_align_arg mpg123_format_none(mpg123_handle *mh)
+{
+	int r;
+	if(mh == NULL) return MPG123_ERR;
+
+	r = mpg123_fmt_none(&mh->p);
+	if(r != MPG123_OK){ mh->err = r; r = MPG123_ERR; }
+
+	return r;
+}
+
+int attribute_align_arg mpg123_fmt_none(mpg123_pars *mp)
+{
+	if(mp == NULL) return MPG123_BAD_PARS;
+
+	if(PVERB(mp,3)) fprintf(stderr, "Note: Disabling all formats.\n");
+
+	memset(mp->audio_caps,0,sizeof(mp->audio_caps));
+	return MPG123_OK;
+}
+
+int attribute_align_arg mpg123_format_all(mpg123_handle *mh)
+{
+	int r;
+	if(mh == NULL) return MPG123_ERR;
+
+	r = mpg123_fmt_all(&mh->p);
+	if(r != MPG123_OK){ mh->err = r; r = MPG123_ERR; }
+
+	return r;
+}
+
+int attribute_align_arg mpg123_fmt_all(mpg123_pars *mp)
+{
+	size_t rate, ch, enc;
+	if(mp == NULL) return MPG123_BAD_PARS;
+
+	if(PVERB(mp,3)) fprintf(stderr, "Note: Enabling all formats.\n");
+
+	for(ch=0;   ch   < NUM_CHANNELS;     ++ch)
+	for(rate=0; rate < MPG123_RATES+1;   ++rate)
+	for(enc=0;  enc  < MPG123_ENCODINGS; ++enc)
+	mp->audio_caps[ch][rate][enc] = good_enc(my_encodings[enc]) ? 1 : 0;
+
+	return MPG123_OK;
+}
+
+int attribute_align_arg mpg123_format(mpg123_handle *mh, long rate, int channels, int encodings)
+{
+	int r;
+	if(mh == NULL) return MPG123_ERR;
+	r = mpg123_fmt(&mh->p, rate, channels, encodings);
+	if(r != MPG123_OK){ mh->err = r; r = MPG123_ERR; }
+
+	return r;
+}
+
+int attribute_align_arg mpg123_fmt(mpg123_pars *mp, long rate, int channels, int encodings)
+{
+	int ie, ic, ratei;
+	int ch[2] = {0, 1};
+	if(mp == NULL) return MPG123_BAD_PARS;
+	if(!(channels & (MPG123_MONO|MPG123_STEREO))) return MPG123_BAD_CHANNEL;
+
+	if(PVERB(mp,3)) fprintf(stderr, "Note: Want to enable format %li/%i for encodings 0x%x.\n", rate, channels, encodings);
+
+	if(!(channels & MPG123_STEREO)) ch[1] = 0;     /* {0,0} */
+	else if(!(channels & MPG123_MONO)) ch[0] = 1; /* {1,1} */
+	ratei = rate2num(mp, rate);
+	if(ratei < 0) return MPG123_BAD_RATE;
+
+	/* now match the encodings */
+	for(ic = 0; ic < 2; ++ic)
+	{
+		for(ie = 0; ie < MPG123_ENCODINGS; ++ie)
+		if(good_enc(my_encodings[ie]) && ((my_encodings[ie] & encodings) == my_encodings[ie]))
+		mp->audio_caps[ch[ic]][ratei][ie] = 1;
+
+		if(ch[0] == ch[1]) break; /* no need to do it again */
+	}
+
+	return MPG123_OK;
+}
+
+int attribute_align_arg mpg123_format_support(mpg123_handle *mh, long rate, int encoding)
+{
+	if(mh == NULL) return 0;
+	else return mpg123_fmt_support(&mh->p, rate, encoding);
+}
+
+int attribute_align_arg mpg123_fmt_support(mpg123_pars *mp, long rate, int encoding)
+{
+	int ch = 0;
+	int ratei, enci;
+	ratei = rate2num(mp, rate);
+	enci  = enc2num(encoding);
+	if(mp == NULL || ratei < 0 || enci < 0) return 0;
+	if(mp->audio_caps[0][ratei][enci]) ch |= MPG123_MONO;
+	if(mp->audio_caps[1][ratei][enci]) ch |= MPG123_STEREO;
+	return ch;
+}
+
+/* Call this one to ensure that any valid format will be something different than this. */
+void invalidate_format(struct audioformat *af)
+{
+	af->encoding = 0;
+	af->rate     = 0;
+	af->channels = 0;
+}
+