* IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
* *
* THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2001 *
- * by the XIPHOPHORUS Company http://www.xiph.org/ *
+ * by the Xiph.Org Foundation http://www.xiph.org/ *
* *
********************************************************************
function: vorbis encode-engine setup
- last mod: $Id$
********************************************************************/
+/** \file
+ * Libvorbisenc is a convenient API for setting up an encoding
+ * environment using libvorbis. Libvorbisenc encapsulates the
+ * actions needed to set up the encoder properly.
+ */
+
#ifndef _OV_ENC_H_
#define _OV_ENC_H_
#include "codec.h"
+/**
+ * This is the primary function within libvorbisenc for setting up managed
+ * bitrate modes.
+ *
+ * Before this function is called, the \ref vorbis_info
+ * struct should be initialized by using vorbis_info_init() from the libvorbis
+ * API. After encoding, vorbis_info_clear() should be called.
+ *
+ * The max_bitrate, nominal_bitrate, and min_bitrate settings are used to set
+ * constraints for the encoded file. This function uses these settings to
+ * select the appropriate encoding mode and set it up.
+ *
+ * \param vi Pointer to an initialized \ref vorbis_info struct.
+ * \param channels The number of channels to be encoded.
+ * \param rate The sampling rate of the source audio.
+ * \param max_bitrate Desired maximum bitrate (limit). -1 indicates unset.
+ * \param nominal_bitrate Desired average, or central, bitrate. -1 indicates unset.
+ * \param min_bitrate Desired minimum bitrate. -1 indicates unset.
+ *
+ * \return Zero for success, and negative values for failure.
+ *
+ * \retval 0 Success.
+ * \retval OV_EFAULT Internal logic fault; indicates a bug or heap/stack corruption.
+ * \retval OV_EINVAL Invalid setup request, eg, out of range argument.
+ * \retval OV_EIMPL Unimplemented mode; unable to comply with bitrate request.
+ */
extern int vorbis_encode_init(vorbis_info *vi,
- long channels,
- long rate,
-
- long max_bitrate,
- long nominal_bitrate,
- long min_bitrate);
+ long channels,
+ long rate,
+
+ long max_bitrate,
+ long nominal_bitrate,
+ long min_bitrate);
+/**
+ * This function performs step-one of a three-step bitrate-managed encode
+ * setup. It functions similarly to the one-step setup performed by \ref
+ * vorbis_encode_init but allows an application to make further encode setup
+ * tweaks using \ref vorbis_encode_ctl before finally calling \ref
+ * vorbis_encode_setup_init to complete the setup process.
+ *
+ * Before this function is called, the \ref vorbis_info struct should be
+ * initialized by using vorbis_info_init() from the libvorbis API. After
+ * encoding, vorbis_info_clear() should be called.
+ *
+ * The max_bitrate, nominal_bitrate, and min_bitrate settings are used to set
+ * constraints for the encoded file. This function uses these settings to
+ * select the appropriate encoding mode and set it up.
+ *
+ * \param vi Pointer to an initialized vorbis_info struct.
+ * \param channels The number of channels to be encoded.
+ * \param rate The sampling rate of the source audio.
+ * \param max_bitrate Desired maximum bitrate (limit). -1 indicates unset.
+ * \param nominal_bitrate Desired average, or central, bitrate. -1 indicates unset.
+ * \param min_bitrate Desired minimum bitrate. -1 indicates unset.
+ *
+ * \return Zero for success, and negative for failure.
+ *
+ * \retval 0 Success
+ * \retval OV_EFAULT Internal logic fault; indicates a bug or heap/stack corruption.
+ * \retval OV_EINVAL Invalid setup request, eg, out of range argument.
+ * \retval OV_EIMPL Unimplemented mode; unable to comply with bitrate request.
+ */
extern int vorbis_encode_setup_managed(vorbis_info *vi,
- long channels,
- long rate,
-
- long max_bitrate,
- long nominal_bitrate,
- long min_bitrate);
-
+ long channels,
+ long rate,
+
+ long max_bitrate,
+ long nominal_bitrate,
+ long min_bitrate);
+
+/**
+ * This function performs step-one of a three-step variable bitrate
+ * (quality-based) encode setup. It functions similarly to the one-step setup
+ * performed by \ref vorbis_encode_init_vbr() but allows an application to
+ * make further encode setup tweaks using \ref vorbis_encode_ctl() before
+ * finally calling \ref vorbis_encode_setup_init to complete the setup
+ * process.
+ *
+ * Before this function is called, the \ref vorbis_info struct should be
+ * initialized by using \ref vorbis_info_init() from the libvorbis API. After
+ * encoding, vorbis_info_clear() should be called.
+ *
+ * \param vi Pointer to an initialized vorbis_info struct.
+ * \param channels The number of channels to be encoded.
+ * \param rate The sampling rate of the source audio.
+ * \param quality Desired quality level, currently from -0.1 to 1.0 (lo to hi).
+ *
+ * \return Zero for success, and negative values for failure.
+ *
+ * \retval 0 Success
+ * \retval OV_EFAULT Internal logic fault; indicates a bug or heap/stack corruption.
+ * \retval OV_EINVAL Invalid setup request, eg, out of range argument.
+ * \retval OV_EIMPL Unimplemented mode; unable to comply with quality level request.
+ */
extern int vorbis_encode_setup_vbr(vorbis_info *vi,
- long channels,
- long rate,
-
- float /* quality level from 0. (lo) to 1. (hi) */
- );
+ long channels,
+ long rate,
+
+ float quality
+ );
+/**
+ * This is the primary function within libvorbisenc for setting up variable
+ * bitrate ("quality" based) modes.
+ *
+ *
+ * Before this function is called, the vorbis_info struct should be
+ * initialized by using vorbis_info_init() from the libvorbis API. After
+ * encoding, vorbis_info_clear() should be called.
+ *
+ * \param vi Pointer to an initialized vorbis_info struct.
+ * \param channels The number of channels to be encoded.
+ * \param rate The sampling rate of the source audio.
+ * \param base_quality Desired quality level, currently from -0.1 to 1.0 (lo to hi).
+ *
+ *
+ * \return Zero for success, or a negative number for failure.
+ *
+ * \retval 0 Success
+ * \retval OV_EFAULT Internal logic fault; indicates a bug or heap/stack corruption.
+ * \retval OV_EINVAL Invalid setup request, eg, out of range argument.
+ * \retval OV_EIMPL Unimplemented mode; unable to comply with quality level request.
+ */
extern int vorbis_encode_init_vbr(vorbis_info *vi,
- long channels,
- long rate,
-
- float base_quality /* quality level from 0. (lo) to 1. (hi) */
- );
+ long channels,
+ long rate,
+ float base_quality
+ );
+
+/**
+ * This function performs the last stage of three-step encoding setup, as
+ * described in the API overview under managed bitrate modes.
+ *
+ * Before this function is called, the \ref vorbis_info struct should be
+ * initialized by using vorbis_info_init() from the libvorbis API, one of
+ * \ref vorbis_encode_setup_managed() or \ref vorbis_encode_setup_vbr() called to
+ * initialize the high-level encoding setup, and \ref vorbis_encode_ctl()
+ * called if necessary to make encoding setup changes.
+ * vorbis_encode_setup_init() finalizes the highlevel encoding structure into
+ * a complete encoding setup after which the application may make no further
+ * setup changes.
+ *
+ * After encoding, vorbis_info_clear() should be called.
+ *
+ * \param vi Pointer to an initialized \ref vorbis_info struct.
+ *
+ * \return Zero for success, and negative values for failure.
+ *
+ * \retval 0 Success.
+ * \retval OV_EFAULT Internal logic fault; indicates a bug or heap/stack corruption.
+ *
+ * \retval OV_EINVAL Attempt to use vorbis_encode_setup_init() without first
+ * calling one of vorbis_encode_setup_managed() or vorbis_encode_setup_vbr() to
+ * initialize the high-level encoding setup
+ *
+ */
extern int vorbis_encode_setup_init(vorbis_info *vi);
+/**
+ * This function implements a generic interface to miscellaneous encoder
+ * settings similar to the classic UNIX 'ioctl()' system call. Applications
+ * may use vorbis_encode_ctl() to query or set bitrate management or quality
+ * mode details by using one of several \e request arguments detailed below.
+ * vorbis_encode_ctl() must be called after one of
+ * vorbis_encode_setup_managed() or vorbis_encode_setup_vbr(). When used
+ * to modify settings, \ref vorbis_encode_ctl() must be called before \ref
+ * vorbis_encode_setup_init().
+ *
+ * \param vi Pointer to an initialized vorbis_info struct.
+ *
+ * \param number Specifies the desired action; See \ref encctlcodes "the list
+ * of available requests".
+ *
+ * \param arg void * pointing to a data structure matching the request
+ * argument.
+ *
+ * \retval 0 Success. Any further return information (such as the result of a
+ * query) is placed into the storage pointed to by *arg.
+ *
+ * \retval OV_EINVAL Invalid argument, or an attempt to modify a setting after
+ * calling vorbis_encode_setup_init().
+ *
+ * \retval OV_EIMPL Unimplemented or unknown request
+ */
extern int vorbis_encode_ctl(vorbis_info *vi,int number,void *arg);
- /* deprecated rate management supported only for compatability */
-#define OV_ECTL_RATEMANAGE_GET 0x10
-#define OV_ECTL_RATEMANAGE_SET 0x11
-#define OV_ECTL_RATEMANAGE_AVG 0x12
-#define OV_ECTL_RATEMANAGE_HARD 0x13
-
+/**
+ * \deprecated This is a deprecated interface. Please use vorbis_encode_ctl()
+ * with the \ref ovectl_ratemanage2_arg struct and \ref
+ * OV_ECTL_RATEMANAGE2_GET and \ref OV_ECTL_RATEMANAGE2_SET calls in new code.
+ *
+ * The \ref ovectl_ratemanage_arg structure is used with vorbis_encode_ctl()
+ * and the \ref OV_ECTL_RATEMANAGE_GET, \ref OV_ECTL_RATEMANAGE_SET, \ref
+ * OV_ECTL_RATEMANAGE_AVG, \ref OV_ECTL_RATEMANAGE_HARD calls in order to
+ * query and modify specifics of the encoder's bitrate management
+ * configuration.
+*/
struct ovectl_ratemanage_arg {
- int management_active;
-
+ int management_active; /**< nonzero if bitrate management is active*/
+/** hard lower limit (in kilobits per second) below which the stream bitrate
+ will never be allowed for any given bitrate_hard_window seconds of time.*/
long bitrate_hard_min;
+/** hard upper limit (in kilobits per second) above which the stream bitrate
+ will never be allowed for any given bitrate_hard_window seconds of time.*/
long bitrate_hard_max;
+/** the window period (in seconds) used to regulate the hard bitrate minimum
+ and maximum*/
double bitrate_hard_window;
-
+/** soft lower limit (in kilobits per second) below which the average bitrate
+ tracker will start nudging the bitrate higher.*/
long bitrate_av_lo;
+/** soft upper limit (in kilobits per second) above which the average bitrate
+ tracker will start nudging the bitrate lower.*/
long bitrate_av_hi;
+/** the window period (in seconds) used to regulate the average bitrate
+ minimum and maximum.*/
double bitrate_av_window;
+/** Regulates the relative centering of the average and hard windows; in
+ libvorbis 1.0 and 1.0.1, the hard window regulation overlapped but
+ followed the average window regulation. In libvorbis 1.1 a bit-reservoir
+ interface replaces the old windowing interface; the older windowing
+ interface is simulated and this field has no effect.*/
double bitrate_av_window_center;
};
-
- /* new rate setup */
-#define OV_ECTL_RATEMANAGE2_GET 0x14
-#define OV_ECTL_RATEMANAGE2_SET 0x15
-
+/**
+ * \name struct ovectl_ratemanage2_arg
+ *
+ * The ovectl_ratemanage2_arg structure is used with vorbis_encode_ctl() and
+ * the OV_ECTL_RATEMANAGE2_GET and OV_ECTL_RATEMANAGE2_SET calls in order to
+ * query and modify specifics of the encoder's bitrate management
+ * configuration.
+ *
+*/
struct ovectl_ratemanage2_arg {
- int management_active;
-
+ int management_active; /**< nonzero if bitrate management is active */
+/** Lower allowed bitrate limit in kilobits per second */
long bitrate_limit_min_kbps;
+/** Upper allowed bitrate limit in kilobits per second */
long bitrate_limit_max_kbps;
- long bitrate_limit_reservoir_bits;
+ long bitrate_limit_reservoir_bits; /**<Size of the bitrate reservoir in bits */
+/** Regulates the bitrate reservoir's preferred fill level in a range from 0.0
+ * to 1.0; 0.0 tries to bank bits to buffer against future bitrate spikes, 1.0
+ * buffers against future sudden drops in instantaneous bitrate. Default is
+ * 0.1
+ */
double bitrate_limit_reservoir_bias;
-
+/** Average bitrate setting in kilobits per second */
long bitrate_average_kbps;
+/** Slew rate limit setting for average bitrate adjustment; sets the minimum
+ * time in seconds the bitrate tracker may swing from one extreme to the
+ * other when boosting or damping average bitrate.
+ */
double bitrate_average_damping;
};
+/**
+ * \name vorbis_encode_ctl() codes
+ *
+ * \anchor encctlcodes
+ *
+ * These values are passed as the \c number parameter of vorbis_encode_ctl().
+ * The type of the referent of that function's \c arg pointer depends on these
+ * codes.
+ */
+/*@{*/
+/**
+ * Query the current encoder bitrate management setting.
+ *
+ *Argument: <tt>struct ovectl_ratemanage2_arg *</tt>
+ *
+ * Used to query the current encoder bitrate management setting. Also used to
+ * initialize fields of an ovectl_ratemanage2_arg structure for use with
+ * \ref OV_ECTL_RATEMANAGE2_SET.
+ */
+#define OV_ECTL_RATEMANAGE2_GET 0x14
+
+/**
+ * Set the current encoder bitrate management settings.
+ *
+ * Argument: <tt>struct ovectl_ratemanage2_arg *</tt>
+ *
+ * Used to set the current encoder bitrate management settings to the values
+ * listed in the ovectl_ratemanage2_arg. Passing a NULL pointer will disable
+ * bitrate management.
+*/
+#define OV_ECTL_RATEMANAGE2_SET 0x15
+
+/**
+ * Returns the current encoder hard-lowpass setting (kHz) in the double
+ * pointed to by arg.
+ *
+ * Argument: <tt>double *</tt>
+*/
#define OV_ECTL_LOWPASS_GET 0x20
+
+/**
+ * Sets the encoder hard-lowpass to the value (kHz) pointed to by arg. Valid
+ * lowpass settings range from 2 to 99.
+ *
+ * Argument: <tt>double *</tt>
+*/
#define OV_ECTL_LOWPASS_SET 0x21
+/**
+ * Returns the current encoder impulse block setting in the double pointed
+ * to by arg.
+ *
+ * Argument: <tt>double *</tt>
+*/
#define OV_ECTL_IBLOCK_GET 0x30
+
+/**
+ * Sets the impulse block bias to the the value pointed to by arg.
+ *
+ * Argument: <tt>double *</tt>
+ *
+ * Valid range is -15.0 to 0.0 [default]. A negative impulse block bias will
+ * direct to encoder to use more bits when incoding short blocks that contain
+ * strong impulses, thus improving the accuracy of impulse encoding.
+ */
#define OV_ECTL_IBLOCK_SET 0x31
+/**
+ * Returns the current encoder coupling setting in the int pointed
+ * to by arg.
+ *
+ * Argument: <tt>int *</tt>
+*/
+#define OV_ECTL_COUPLING_GET 0x40
+
+/**
+ * Enables/disables channel coupling in multichannel encoding according to arg.
+ *
+ * Argument: <tt>int *</tt>
+ *
+ * Zero disables channel coupling for multichannel inputs, nonzer enables
+ * channel coupling. Setting has no effect on monophonic encoding or
+ * multichannel counts that do not offer coupling. At present, coupling is
+ * available for stereo and 5.1 encoding.
+ */
+#define OV_ECTL_COUPLING_SET 0x41
+
+ /* deprecated rate management supported only for compatibility */
+
+/**
+ * Old interface to querying bitrate management settings.
+ *
+ * Deprecated after move to bit-reservoir style management in 1.1 rendered
+ * this interface partially obsolete.
+
+ * \deprecated Please use \ref OV_ECTL_RATEMANAGE2_GET instead.
+ *
+ * Argument: <tt>struct ovectl_ratemanage_arg *</tt>
+ */
+#define OV_ECTL_RATEMANAGE_GET 0x10
+/**
+ * Old interface to modifying bitrate management settings.
+ *
+ * deprecated after move to bit-reservoir style management in 1.1 rendered
+ * this interface partially obsolete.
+ *
+ * \deprecated Please use \ref OV_ECTL_RATEMANAGE2_SET instead.
+ *
+ * Argument: <tt>struct ovectl_ratemanage_arg *</tt>
+ */
+#define OV_ECTL_RATEMANAGE_SET 0x11
+/**
+ * Old interface to setting average-bitrate encoding mode.
+ *
+ * Deprecated after move to bit-reservoir style management in 1.1 rendered
+ * this interface partially obsolete.
+ *
+ * \deprecated Please use \ref OV_ECTL_RATEMANAGE2_SET instead.
+ *
+ * Argument: <tt>struct ovectl_ratemanage_arg *</tt>
+ */
+#define OV_ECTL_RATEMANAGE_AVG 0x12
+/**
+ * Old interface to setting bounded-bitrate encoding modes.
+ *
+ * deprecated after move to bit-reservoir style management in 1.1 rendered
+ * this interface partially obsolete.
+ *
+ * \deprecated Please use \ref OV_ECTL_RATEMANAGE2_SET instead.
+ *
+ * Argument: <tt>struct ovectl_ratemanage_arg *</tt>
+ */
+#define OV_ECTL_RATEMANAGE_HARD 0x13
+
+/*@}*/
+
+
+
#ifdef __cplusplus
}
#endif /* __cplusplus */
#endif
-
-