TABLE OF CONTENTS

        AHX_DecodeFrame -- Decode one frame of a tune.

        Length = AHX_DecodeFrame( AHX, Buffer1, Buffer2, BufferModulo, BitsPerSample )

        ULONG AHX_DecoceFrame( APTR, BYTE *, BYTE *, LONG, LONG );

        Decodes one frame from a tune to sample buffers. Sample buffers
        must be able to store at least Frequency/50 samples each.
        BufferModulo specifies an offset (in bytes) for a next sample.

        When decoding in mono both Buffer1 and Buffer2 can be same.

        AHX - pointer to an AHX handle
        Buffer1 - pointer to the first sample buffer
        Buffer2 - pointer to the second sample buffer
        BufferModulo - offset to the next sample
        BitsPerSample - choose 16 for now

        Length - Number of decoded samples per channel

        /* Decode one frame of 16bit stereo data */
        BYTE buffer[48000/50*sizeof(WORD)*2];

        AHX_SetAttrs(AHX, AHXPLAY_Frequency, 48000, TAG_DONE);
        AHX_Decode(AHX, &buffer, &buffer + sizeof(WORD), 4, 16);

        /* Decode one frame of 16bit mono data */
        BYTE buffer[48000/50*sizeof(WORD)];

        AHX_SetAttrs(AHX, AHXPLAY_Frequency, 48000, AHXPLAY_ForceMono, TRUE, TAG_DONE);
        AHX_Decode(AHX, &buffer, &buffer, 2, 16);

        AHX_GetAttr -- Inquire AHX tune information

        success = AHX_GetAttr( AttrID, AHX, StoragePtr )

        ULONG AHX_GetAttr( ULONG, APTR, ULONG * );

        Inquires AHX tune information.

        AttrID - an attribute to get.
        AHX - pointer to an AHX handle
        StoragePtr - the address of the storage variable

        success - returns 0 if the attribute was not supported, non-zero
            if StoragePtr contains meaningful data.

        AHX_LoadTagList(), AHX_SetAttrsA()

        AHX_InitSubsong -- Initialize chosen subsong.

        success = AHX_InitSubsong( AHX, SongNumber )

        ULONG AHX_InitSubsong( APTR, ULONG );

        Initializes chosen subsong and moves decoding to start from this
        subsong. If subsong number doesn't exist this function does
        nothing.

        AHX - pointer to an AHX handle
        SongNumber - number of new song. Choose 0 for the default song.

        success - non-zero for success and 0 if song didn't exist.

        AHX_LoadTagList -- Initialize an AHX tune.
        AHX_LoadTags -- Varargs stub for AHX_LoadTagList.

        AHX = AHX_LoadTagList( Tune, Length, TagItems )

        APTR AHX_LoadTagList( APTR, ULONG, CONST struct TagItem * );

        AHX = AHX_LoadTags( Tune, Length, Tag1, ... )

        APTR AHX_LoadTags( APTR, ULONG, ULONG, ... );

        Initialize an AHX tune for decoding and returns an AHX handler
        for future references.

        Tune - pointer to start of complete AHX song data
        Length - size of tune in bytes
        TagList - pointer to an array of TagItem structurres, terminated
            by the value TAG_END. See AHX_SetAttrsA() for tag values.

        AHX - a handle for future references or NULL if an error occurred

        This function calls AHX_InitSubsong(ahx, 0) before returning. Thus
        you can start decoding immediately.

        AHX_Unload(), AHX_SetAttrsA(), AHX_GetAttr(), AHX_InitSubsong()

        AHX_Seek -- Change decoding position.

        newposition = AHX_Seek( AHX, Position )

        ULONG AHX_Seek( APTR, ULONG );

        Changes decoding position in the current subsong to start from
        position specified in seconds. Position is always relative to
        the start of current song and there is no upper limit for the
        position.

        AHX - pointer to an AHX handle.
        Position - new position (granularity is in seconds)

        newposition - new decoding position in seconds

        AHX_SetAttrsA -- Specify attribute values for an AHX tune.
        AHX_SetAttrs -- Varargs stub for AHX_SetAttrsA().

        AHX_SetAttrsA( AHX, TagList )

        VOID AHX_SetAttrsA( APTR, CONST struct TagItem * );

        AHX_SetAttrs( AHX, Tag1, ... )

        VOID AHX_SetAttrs( APTR, ULONG, ... );

        Set playback attributes for an AHX tune.

        AHX - pointer to an AHX handle
        TagList - pointer to an array of TagItem structurres, terminated
            by the value TAG_END. Valid tags are:

        AHXPLAY_Frequency (defaults to 44100)
            Set decoding frequency.

        AHXPLAY_ForceMono (defaults to FALSE)
            Force mono decoding. When set both channels contain same
            sample data.

        AHX_LoadTagList(), AHX_GetAttr()

        AHX_Test -- Test if valid AHX tune.

        success = AHX_Test( Buffer, Length, FileSize )

        ULONG AHX_Test( UBYTE *, ULONG, ULONG );

        Test if the buffer contains valid AHX information. If the tune
        information is valid non-zero result code is returned. You must
        provide at least 64 first bytes of an AHX tune for analysis.

        Buffer - pointer to the AHX header snapshot.
        Length - length of the AHX header snapshot.
        FileSize - length of the AHX tune in total.

        success  - non-zero if valid AHX header

        AHX_Unload -- Unload the AHX tune from memory

        AHX_Unload( AHX )

        VOID AHX_Unload( APTR );

        Unloads the AHX tune and frees associated memory.

        It is safe to pass a NULL instead of a handle.

        AHX - pointer to an AHX handle