Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 786 insertions, 0 deletions

diff --git a/media/libtheora/include/theora/theora.h b/media/libtheora/include/theora/theora.h
new file mode 100644
index 0000000000..a729a76890
--- /dev/null
+++ b/media/libtheora/include/theora/theora.h
@@ -0,0 +1,786 @@
+/********************************************************************
+ *                                                                  *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE.   *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
+ *                                                                  *
+ * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009                *
+ * by the Xiph.Org Foundation http://www.xiph.org/                  *
+ *                                                                  *
+ ********************************************************************
+
+  function:
+  last mod: $Id: theora.h,v 1.17 2003/12/06 18:06:19 arc Exp $
+
+ ********************************************************************/
+
+#ifndef _O_THEORA_H_
+#define _O_THEORA_H_
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif /* __cplusplus */
+
+#include <stddef.h>	/* for size_t */
+
+#include <ogg/ogg.h>
+
+/** \file
+ * The libtheora pre-1.0 legacy C API.
+ *
+ * \ingroup oldfuncs
+ *
+ * \section intro Introduction
+ *
+ * This is the documentation for the libtheora legacy C API, declared in
+ * the theora.h header, which describes the old interface used before
+ * the 1.0 release. This API was widely deployed for several years and
+ * remains supported, but for new code we recommend the cleaner API
+ * declared in theoradec.h and theoraenc.h.
+ *
+ * libtheora is the reference implementation for
+ * <a href="http://www.theora.org/">Theora</a>, a free video codec.
+ * Theora is derived from On2's VP3 codec with improved integration with
+ * Ogg multimedia formats by <a href="http://www.xiph.org/">Xiph.Org</a>.
+ *
+ * \section overview Overview
+ *
+ * This library will both decode and encode theora packets to/from raw YUV
+ * frames.  In either case, the packets will most likely either come from or
+ * need to be embedded in an Ogg stream.  Use
+ * <a href="http://xiph.org/ogg/">libogg</a> or
+ * <a href="http://www.annodex.net/software/liboggz/index.html">liboggz</a>
+ * to extract/package these packets.
+ *
+ * \section decoding Decoding Process
+ *
+ * Decoding can be separated into the following steps:
+ * -# initialise theora_info and theora_comment structures using
+ *    theora_info_init() and theora_comment_init():
+ \verbatim
+ theora_info     info;
+ theora_comment  comment;
+
+ theora_info_init(&info);
+ theora_comment_init(&comment);
+ \endverbatim
+ * -# retrieve header packets from Ogg stream (there should be 3) and decode
+ *    into theora_info and theora_comment structures using
+ *    theora_decode_header().  See \ref identification for more information on
+ *    identifying which packets are theora packets.
+ \verbatim
+ int i;
+ for (i = 0; i < 3; i++)
+ {
+   (get a theora packet "op" from the Ogg stream)
+   theora_decode_header(&info, &comment, op);
+ }
+ \endverbatim
+ * -# initialise the decoder based on the information retrieved into the
+ *    theora_info struct by theora_decode_header().  You will need a
+ *    theora_state struct.
+ \verbatim
+ theora_state state;
+
+ theora_decode_init(&state, &info);
+ \endverbatim
+ * -# pass in packets and retrieve decoded frames!  See the yuv_buffer
+ *    documentation for information on how to retrieve raw YUV data.
+ \verbatim
+ yuf_buffer buffer;
+ while (last packet was not e_o_s) {
+   (get a theora packet "op" from the Ogg stream)
+   theora_decode_packetin(&state, op);
+   theora_decode_YUVout(&state, &buffer);
+ }
+ \endverbatim
+ *
+ *
+ * \subsection identification Identifying Theora Packets
+ *
+ * All streams inside an Ogg file have a unique serial_no attached to the
+ * stream.  Typically, you will want to
+ *  - retrieve the serial_no for each b_o_s (beginning of stream) page
+ *    encountered within the Ogg file;
+ *  - test the first (only) packet on that page to determine if it is a theora
+ *    packet;
+ *  - once you have found a theora b_o_s page then use the retrieved serial_no
+ *    to identify future packets belonging to the same theora stream.
+ *
+ * Note that you \e cannot use theora_packet_isheader() to determine if a
+ * packet is a theora packet or not, as this function does not perform any
+ * checking beyond whether a header bit is present.  Instead, use the
+ * theora_decode_header() function and check the return value; or examine the
+ * header bytes at the beginning of the Ogg page.
+ */
+
+
+/** \defgroup oldfuncs Legacy pre-1.0 C API */
+/*  @{ */
+
+/**
+ * A YUV buffer for passing uncompressed frames to and from the codec.
+ * This holds a Y'CbCr frame in planar format. The CbCr planes can be
+ * subsampled and have their own separate dimensions and row stride
+ * offsets. Note that the strides may be negative in some
+ * configurations. For theora the width and height of the largest plane
+ * must be a multiple of 16. The actual meaningful picture size and
+ * offset are stored in the theora_info structure; frames returned by
+ * the decoder may need to be cropped for display.
+ *
+ * All samples are 8 bits. Within each plane samples are ordered by
+ * row from the top of the frame to the bottom. Within each row samples
+ * are ordered from left to right.
+ *
+ * During decode, the yuv_buffer struct is allocated by the user, but all
+ * fields (including luma and chroma pointers) are filled by the library.
+ * These pointers address library-internal memory and their contents should
+ * not be modified.
+ *
+ * Conversely, during encode the user allocates the struct and fills out all
+ * fields.  The user also manages the data addressed by the luma and chroma
+ * pointers.  See the encoder_example.c and dump_video.c example files in
+ * theora/examples/ for more information.
+ */
+typedef struct {
+    int   y_width;      /**< Width of the Y' luminance plane */
+    int   y_height;     /**< Height of the luminance plane */
+    int   y_stride;     /**< Offset in bytes between successive rows */
+
+    int   uv_width;     /**< Width of the Cb and Cr chroma planes */
+    int   uv_height;    /**< Height of the chroma planes */
+    int   uv_stride;    /**< Offset between successive chroma rows */
+    unsigned char *y;   /**< Pointer to start of luminance data */
+    unsigned char *u;   /**< Pointer to start of Cb data */
+    unsigned char *v;   /**< Pointer to start of Cr data */
+
+} yuv_buffer;
+
+/**
+ * A Colorspace.
+ */
+typedef enum {
+  OC_CS_UNSPECIFIED,    /**< The colorspace is unknown or unspecified */
+  OC_CS_ITU_REC_470M,   /**< This is the best option for 'NTSC' content */
+  OC_CS_ITU_REC_470BG,  /**< This is the best option for 'PAL' content */
+  OC_CS_NSPACES         /**< This marks the end of the defined colorspaces */
+} theora_colorspace;
+
+/**
+ * A Chroma subsampling
+ *
+ * These enumerate the available chroma subsampling options supported
+ * by the theora format. See Section 4.4 of the specification for
+ * exact definitions.
+ */
+typedef enum {
+  OC_PF_420,    /**< Chroma subsampling by 2 in each direction (4:2:0) */
+  OC_PF_RSVD,   /**< Reserved value */
+  OC_PF_422,    /**< Horizonatal chroma subsampling by 2 (4:2:2) */
+  OC_PF_444     /**< No chroma subsampling at all (4:4:4) */
+} theora_pixelformat;
+
+/**
+ * Theora bitstream info.
+ * Contains the basic playback parameters for a stream,
+ * corresponding to the initial 'info' header packet.
+ *
+ * Encoded theora frames must be a multiple of 16 in width and height.
+ * To handle other frame sizes, a crop rectangle is specified in
+ * frame_height and frame_width, offset_x and * offset_y. The offset
+ * and size should still be a multiple of 2 to avoid chroma sampling
+ * shifts. Offset values in this structure are measured from the
+ * upper left of the image.
+ *
+ * Frame rate, in frames per second, is stored as a rational
+ * fraction. Aspect ratio is also stored as a rational fraction, and
+ * refers to the aspect ratio of the frame pixels, not of the
+ * overall frame itself.
+ *
+ * See <a href="http://svn.xiph.org/trunk/theora/examples/encoder_example.c">
+ * examples/encoder_example.c</a> for usage examples of the
+ * other parameters and good default settings for the encoder parameters.
+ */
+typedef struct {
+  ogg_uint32_t  width;		/**< encoded frame width  */
+  ogg_uint32_t  height;		/**< encoded frame height */
+  ogg_uint32_t  frame_width;	/**< display frame width  */
+  ogg_uint32_t  frame_height;	/**< display frame height */
+  ogg_uint32_t  offset_x;	/**< horizontal offset of the displayed frame */
+  ogg_uint32_t  offset_y;	/**< vertical offset of the displayed frame */
+  ogg_uint32_t  fps_numerator;	    /**< frame rate numerator **/
+  ogg_uint32_t  fps_denominator;    /**< frame rate denominator **/
+  ogg_uint32_t  aspect_numerator;   /**< pixel aspect ratio numerator */
+  ogg_uint32_t  aspect_denominator; /**< pixel aspect ratio denominator */
+  theora_colorspace colorspace;	    /**< colorspace */
+  int           target_bitrate;	    /**< nominal bitrate in bits per second */
+  int           quality;  /**< Nominal quality setting, 0-63 */
+  int           quick_p;  /**< Quick encode/decode */
+
+  /* decode only */
+  unsigned char version_major;
+  unsigned char version_minor;
+  unsigned char version_subminor;
+
+  void *codec_setup;
+
+  /* encode only */
+  int           dropframes_p;
+  int           keyframe_auto_p;
+  ogg_uint32_t  keyframe_frequency;
+  ogg_uint32_t  keyframe_frequency_force;  /* also used for decode init to
+                                              get granpos shift correct */
+  ogg_uint32_t  keyframe_data_target_bitrate;
+  ogg_int32_t   keyframe_auto_threshold;
+  ogg_uint32_t  keyframe_mindistance;
+  ogg_int32_t   noise_sensitivity;
+  ogg_int32_t   sharpness;
+
+  theora_pixelformat pixelformat;	/**< chroma subsampling mode to expect */
+
+} theora_info;
+
+/** Codec internal state and context.
+ */
+typedef struct{
+  theora_info *i;
+  ogg_int64_t granulepos;
+
+  void *internal_encode;
+  void *internal_decode;
+
+} theora_state;
+
+/**
+ * Comment header metadata.
+ *
+ * This structure holds the in-stream metadata corresponding to
+ * the 'comment' header packet.
+ *
+ * Meta data is stored as a series of (tag, value) pairs, in
+ * length-encoded string vectors. The first occurence of the
+ * '=' character delimits the tag and value. A particular tag
+ * may occur more than once. The character set encoding for
+ * the strings is always UTF-8, but the tag names are limited
+ * to case-insensitive ASCII. See the spec for details.
+ *
+ * In filling in this structure, theora_decode_header() will
+ * null-terminate the user_comment strings for safety. However,
+ * the bitstream format itself treats them as 8-bit clean,
+ * and so the length array should be treated as authoritative
+ * for their length.
+ */
+typedef struct theora_comment{
+  char **user_comments;         /**< An array of comment string vectors */
+  int   *comment_lengths;       /**< An array of corresponding string vector lengths in bytes */
+  int    comments;              /**< The total number of comment string vectors */
+  char  *vendor;                /**< The vendor string identifying the encoder, null terminated */
+
+} theora_comment;
+
+
+/**\name theora_control() codes */
+/* \anchor decctlcodes_old
+ * These are the available request codes for theora_control()
+ * when called with a decoder instance.
+ * By convention decoder control codes are odd, to distinguish
+ * them from \ref encctlcodes_old "encoder control codes" which
+ * are even.
+ *
+ * Note that since the 1.0 release, both the legacy and the final
+ * implementation accept all the same control codes, but only the
+ * final API declares the newer codes.
+ *
+ * Keep any experimental or vendor-specific values above \c 0x8000.*/
+
+/*@{*/
+
+/**Get the maximum post-processing level.
+ * The decoder supports a post-processing filter that can improve
+ * the appearance of the decoded images. This returns the highest
+ * level setting for this post-processor, corresponding to maximum
+ * improvement and computational expense.
+ */
+#define TH_DECCTL_GET_PPLEVEL_MAX (1)
+
+/**Set the post-processing level.
+ * Sets the level of post-processing to use when decoding the
+ * compressed stream. This must be a value between zero (off)
+ * and the maximum returned by TH_DECCTL_GET_PPLEVEL_MAX.
+ */
+#define TH_DECCTL_SET_PPLEVEL (3)
+
+/**Sets the maximum distance between key frames.
+ * This can be changed during an encode, but will be bounded by
+ *  <tt>1<<th_info#keyframe_granule_shift</tt>.
+ * If it is set before encoding begins, th_info#keyframe_granule_shift will
+ *  be enlarged appropriately.
+ *
+ * \param[in]  buf <tt>ogg_uint32_t</tt>: The maximum distance between key
+ *                   frames.
+ * \param[out] buf <tt>ogg_uint32_t</tt>: The actual maximum distance set.
+ * \retval OC_FAULT  \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(ogg_uint32_t)</tt>.
+ * \retval OC_IMPL   Not supported by this implementation.*/
+#define TH_ENCCTL_SET_KEYFRAME_FREQUENCY_FORCE (4)
+
+/**Set the granule position.
+ * Call this after a seek, to update the internal granulepos
+ * in the decoder, to insure that subsequent frames are marked
+ * properly. If you track timestamps yourself and do not use
+ * the granule postion returned by the decoder, then you do
+ * not need to use this control.
+ */
+#define TH_DECCTL_SET_GRANPOS (5)
+
+/**\anchor encctlcodes_old */
+
+/**Sets the quantization parameters to use.
+ * The parameters are copied, not stored by reference, so they can be freed
+ *  after this call.
+ * <tt>NULL</tt> may be specified to revert to the default parameters.
+ *
+ * \param[in] buf #th_quant_info
+ * \retval OC_FAULT  \a theora_state is <tt>NULL</tt>.
+ * \retval OC_EINVAL Encoding has already begun, the quantization parameters
+ *                    are not acceptable to this version of the encoder,
+ *                    \a buf is <tt>NULL</tt> and \a buf_sz is not zero,
+ *                    or \a buf is non-<tt>NULL</tt> and \a buf_sz is
+ *                    not <tt>sizeof(#th_quant_info)</tt>.
+ * \retval OC_IMPL   Not supported by this implementation.*/
+#define TH_ENCCTL_SET_QUANT_PARAMS (2)
+
+/**Disables any encoder features that would prevent lossless transcoding back
+ *  to VP3.
+ * This primarily means disabling block-level QI values and not using 4MV mode
+ *  when any of the luma blocks in a macro block are not coded.
+ * It also includes using the VP3 quantization tables and Huffman codes; if you
+ *  set them explicitly after calling this function, the resulting stream will
+ *  not be VP3-compatible.
+ * If you enable VP3-compatibility when encoding 4:2:2 or 4:4:4 source
+ *  material, or when using a picture region smaller than the full frame (e.g.
+ *  a non-multiple-of-16 width or height), then non-VP3 bitstream features will
+ *  still be disabled, but the stream will still not be VP3-compatible, as VP3
+ *  was not capable of encoding such formats.
+ * If you call this after encoding has already begun, then the quantization
+ *  tables and codebooks cannot be changed, but the frame-level features will
+ *  be enabled or disabled as requested.
+ *
+ * \param[in]  buf <tt>int</tt>: a non-zero value to enable VP3 compatibility,
+ *                   or 0 to disable it (the default).
+ * \param[out] buf <tt>int</tt>: 1 if all bitstream features required for
+ *                   VP3-compatibility could be set, and 0 otherwise.
+ *                  The latter will be returned if the pixel format is not
+ *                   4:2:0, the picture region is smaller than the full frame,
+ *                   or if encoding has begun, preventing the quantization
+ *                   tables and codebooks from being set.
+ * \retval OC_FAULT  \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval OC_IMPL   Not supported by this implementation.*/
+#define TH_ENCCTL_SET_VP3_COMPATIBLE (10)
+
+/**Gets the maximum speed level.
+ * Higher speed levels favor quicker encoding over better quality per bit.
+ * Depending on the encoding mode, and the internal algorithms used, quality
+ *  may actually improve, but in this case bitrate will also likely increase.
+ * In any case, overall rate/distortion performance will probably decrease.
+ * The maximum value, and the meaning of each value, may change depending on
+ *  the current encoding mode (VBR vs. CQI, etc.).
+ *
+ * \param[out] buf int: The maximum encoding speed level.
+ * \retval OC_FAULT  \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>.
+ * \retval OC_IMPL   Not supported by this implementation in the current
+ *                    encoding mode.*/
+#define TH_ENCCTL_GET_SPLEVEL_MAX (12)
+
+/**Sets the speed level.
+ * By default a speed value of 1 is used.
+ *
+ * \param[in] buf int: The new encoding speed level.
+ *                      0 is slowest, larger values use less CPU.
+ * \retval OC_FAULT  \a theora_state or \a buf is <tt>NULL</tt>.
+ * \retval OC_EINVAL \a buf_sz is not <tt>sizeof(int)</tt>, or the
+ *                    encoding speed level is out of bounds.
+ *                   The maximum encoding speed level may be
+ *                    implementation- and encoding mode-specific, and can be
+ *                    obtained via #TH_ENCCTL_GET_SPLEVEL_MAX.
+ * \retval OC_IMPL   Not supported by this implementation in the current
+ *                    encoding mode.*/
+#define TH_ENCCTL_SET_SPLEVEL (14)
+
+/*@}*/
+
+#define OC_FAULT       -1       /**< General failure */
+#define OC_EINVAL      -10      /**< Library encountered invalid internal data */
+#define OC_DISABLED    -11      /**< Requested action is disabled */
+#define OC_BADHEADER   -20      /**< Header packet was corrupt/invalid */
+#define OC_NOTFORMAT   -21      /**< Packet is not a theora packet */
+#define OC_VERSION     -22      /**< Bitstream version is not handled */
+#define OC_IMPL        -23      /**< Feature or action not implemented */
+#define OC_BADPACKET   -24      /**< Packet is corrupt */
+#define OC_NEWPACKET   -25      /**< Packet is an (ignorable) unhandled extension */
+#define OC_DUPFRAME    1        /**< Packet is a dropped frame */
+
+/**
+ * Retrieve a human-readable string to identify the encoder vendor and version.
+ * \returns A version string.
+ */
+extern const char *theora_version_string(void);
+
+/**
+ * Retrieve a 32-bit version number.
+ * This number is composed of a 16-bit major version, 8-bit minor version
+ * and 8 bit sub-version, composed as follows:
+<pre>
+   (VERSION_MAJOR<<16) + (VERSION_MINOR<<8) + (VERSION_SUB)
+</pre>
+* \returns The version number.
+*/
+extern ogg_uint32_t theora_version_number(void);
+
+/**
+ * Initialize the theora encoder.
+ * \param th The theora_state handle to initialize for encoding.
+ * \param ti A theora_info struct filled with the desired encoding parameters.
+ * \retval 0 Success
+ */
+extern int theora_encode_init(theora_state *th, theora_info *ti);
+
+/**
+ * Submit a YUV buffer to the theora encoder.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param yuv A buffer of YUV data to encode.  Note that both the yuv_buffer
+ *            struct and the luma/chroma buffers within should be allocated by
+ *            the user.
+ * \retval OC_EINVAL Encoder is not ready, or is finished.
+ * \retval -1 The size of the given frame differs from those previously input
+ * \retval 0 Success
+ */
+extern int theora_encode_YUVin(theora_state *t, yuv_buffer *yuv);
+
+/**
+ * Request the next packet of encoded video.
+ * The encoded data is placed in a user-provided ogg_packet structure.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param last_p whether this is the last packet the encoder should produce.
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ *           elements of this structure, including a pointer to encoded
+ *           data. The memory for the encoded data is owned by libtheora.
+ * \retval 0 No internal storage exists OR no packet is ready
+ * \retval -1 The encoding process has completed
+ * \retval 1 Success
+ */
+extern int theora_encode_packetout( theora_state *t, int last_p,
+                                    ogg_packet *op);
+
+/**
+ * Request a packet containing the initial header.
+ * A pointer to the header data is placed in a user-provided ogg_packet
+ * structure.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ *           elements of this structure, including a pointer to the header
+ *           data. The memory for the header data is owned by libtheora.
+ * \retval 0 Success
+ */
+extern int theora_encode_header(theora_state *t, ogg_packet *op);
+
+/**
+ * Request a comment header packet from provided metadata.
+ * A pointer to the comment data is placed in a user-provided ogg_packet
+ * structure.
+ * \param tc A theora_comment structure filled with the desired metadata
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ *           elements of this structure, including a pointer to the encoded
+ *           comment data. The memory for the comment data is owned by
+ *           the application, and must be freed by it using _ogg_free().
+ *           On some systems (such as Windows when using dynamic linking), this
+ *           may mean the free is executed in a different module from the
+ *           malloc, which will crash; there is no way to free this memory on
+ *           such systems.
+ * \retval 0 Success
+ */
+extern int theora_encode_comment(theora_comment *tc, ogg_packet *op);
+
+/**
+ * Request a packet containing the codebook tables for the stream.
+ * A pointer to the codebook data is placed in a user-provided ogg_packet
+ * structure.
+ * \param t A theora_state handle previously initialized for encoding.
+ * \param op An ogg_packet structure to fill. libtheora will set all
+ *           elements of this structure, including a pointer to the codebook
+ *           data. The memory for the header data is owned by libtheora.
+ * \retval 0 Success
+ */
+extern int theora_encode_tables(theora_state *t, ogg_packet *op);
+
+/**
+ * Decode an Ogg packet, with the expectation that the packet contains
+ * an initial header, comment data or codebook tables.
+ *
+ * \param ci A theora_info structure to fill. This must have been previously
+ *           initialized with theora_info_init(). If \a op contains an initial
+ *           header, theora_decode_header() will fill \a ci with the
+ *           parsed header values. If \a op contains codebook tables,
+ *           theora_decode_header() will parse these and attach an internal
+ *           representation to \a ci->codec_setup.
+ * \param cc A theora_comment structure to fill. If \a op contains comment
+ *           data, theora_decode_header() will fill \a cc with the parsed
+ *           comments.
+ * \param op An ogg_packet structure which you expect contains an initial
+ *           header, comment data or codebook tables.
+ *
+ * \retval OC_BADHEADER \a op is NULL; OR the first byte of \a op->packet
+ *                      has the signature of an initial packet, but op is
+ *                      not a b_o_s packet; OR this packet has the signature
+ *                      of an initial header packet, but an initial header
+ *                      packet has already been seen; OR this packet has the
+ *                      signature of a comment packet, but the initial header
+ *                      has not yet been seen; OR this packet has the signature
+ *                      of a comment packet, but contains invalid data; OR
+ *                      this packet has the signature of codebook tables,
+ *                      but the initial header or comments have not yet
+ *                      been seen; OR this packet has the signature of codebook
+ *                      tables, but contains invalid data;
+ *                      OR the stream being decoded has a compatible version
+ *                      but this packet does not have the signature of a
+ *                      theora initial header, comments, or codebook packet
+ * \retval OC_VERSION   The packet data of \a op is an initial header with
+ *                      a version which is incompatible with this version of
+ *                      libtheora.
+ * \retval OC_NEWPACKET the stream being decoded has an incompatible (future)
+ *                      version and contains an unknown signature.
+ * \retval 0            Success
+ *
+ * \note The normal usage is that theora_decode_header() be called on the
+ *       first three packets of a theora logical bitstream in succession.
+ */
+extern int theora_decode_header(theora_info *ci, theora_comment *cc,
+                                ogg_packet *op);
+
+/**
+ * Initialize a theora_state handle for decoding.
+ * \param th The theora_state handle to initialize.
+ * \param c  A theora_info struct filled with the desired decoding parameters.
+ *           This is of course usually obtained from a previous call to
+ *           theora_decode_header().
+ * \retval 0 Success
+ */
+extern int theora_decode_init(theora_state *th, theora_info *c);
+
+/**
+ * Input a packet containing encoded data into the theora decoder.
+ * \param th A theora_state handle previously initialized for decoding.
+ * \param op An ogg_packet containing encoded theora data.
+ * \retval 0 Success
+ * \retval OC_BADPACKET \a op does not contain encoded video data
+ */
+extern int theora_decode_packetin(theora_state *th,ogg_packet *op);
+
+/**
+ * Output the next available frame of decoded YUV data.
+ * \param th A theora_state handle previously initialized for decoding.
+ * \param yuv A yuv_buffer in which libtheora should place the decoded data.
+ *            Note that the buffer struct itself is allocated by the user, but
+ *            that the luma and chroma pointers will be filled in by the
+ *            library.  Also note that these luma and chroma regions should be
+ *            considered read-only by the user.
+ * \retval 0 Success
+ */
+extern int theora_decode_YUVout(theora_state *th,yuv_buffer *yuv);
+
+/**
+ * Report whether a theora packet is a header or not
+ * This function does no verification beyond checking the header
+ * flag bit so it should not be used for bitstream identification;
+ * use theora_decode_header() for that.
+ *
+ * \param op An ogg_packet containing encoded theora data.
+ * \retval 1 The packet is a header packet
+ * \retval 0 The packet is not a header packet (and so contains frame data)
+ *
+ * Thus function was added in the 1.0alpha4 release.
+ */
+extern int theora_packet_isheader(ogg_packet *op);
+
+/**
+ * Report whether a theora packet is a keyframe or not
+ *
+ * \param op An ogg_packet containing encoded theora data.
+ * \retval 1 The packet contains a keyframe image
+ * \retval 0 The packet is contains an interframe delta
+ * \retval -1 The packet is not an image data packet at all
+ *
+ * Thus function was added in the 1.0alpha4 release.
+ */
+extern int theora_packet_iskeyframe(ogg_packet *op);
+
+/**
+ * Report the granulepos shift radix
+ *
+ * When embedded in Ogg, Theora uses a two-part granulepos,
+ * splitting the 64-bit field into two pieces. The more-significant
+ * section represents the frame count at the last keyframe,
+ * and the less-significant section represents the count of
+ * frames since the last keyframe. In this way the overall
+ * field is still non-decreasing with time, but usefully encodes
+ * a pointer to the last keyframe, which is necessary for
+ * correctly restarting decode after a seek.
+ *
+ * This function reports the number of bits used to represent
+ * the distance to the last keyframe, and thus how the granulepos
+ * field must be shifted or masked to obtain the two parts.
+ *
+ * Since libtheora returns compressed data in an ogg_packet
+ * structure, this may be generally useful even if the Theora
+ * packets are not being used in an Ogg container.
+ *
+ * \param ti A previously initialized theora_info struct
+ * \returns The bit shift dividing the two granulepos fields
+ *
+ * This function was added in the 1.0alpha5 release.
+ */
+int theora_granule_shift(theora_info *ti);
+
+/**
+ * Convert a granulepos to an absolute frame index, starting at 0.
+ * The granulepos is interpreted in the context of a given theora_state handle.
+ *
+ * Note that while the granulepos encodes the frame count (i.e. starting
+ * from 1) this call returns the frame index, starting from zero. Thus
+ * One can calculate the presentation time by multiplying the index by
+ * the rate.
+ *
+ * \param th A previously initialized theora_state handle (encode or decode)
+ * \param granulepos The granulepos to convert.
+ * \returns The frame index corresponding to \a granulepos.
+ * \retval -1 The given granulepos is undefined (i.e. negative)
+ *
+ * Thus function was added in the 1.0alpha4 release.
+ */
+extern ogg_int64_t theora_granule_frame(theora_state *th,ogg_int64_t granulepos);
+
+/**
+ * Convert a granulepos to absolute time in seconds. The granulepos is
+ * interpreted in the context of a given theora_state handle, and gives
+ * the end time of a frame's presentation as used in Ogg mux ordering.
+ *
+ * \param th A previously initialized theora_state handle (encode or decode)
+ * \param granulepos The granulepos to convert.
+ * \returns The absolute time in seconds corresponding to \a granulepos.
+ *          This is the "end time" for the frame, or the latest time it should
+ *           be displayed.
+ *          It is not the presentation time.
+ * \retval -1. The given granulepos is undefined (i.e. negative).
+ */
+extern double theora_granule_time(theora_state *th,ogg_int64_t granulepos);
+
+/**
+ * Initialize a theora_info structure. All values within the given theora_info
+ * structure are initialized, and space is allocated within libtheora for
+ * internal codec setup data.
+ * \param c A theora_info struct to initialize.
+ */
+extern void theora_info_init(theora_info *c);
+
+/**
+ * Clear a theora_info structure. All values within the given theora_info
+ * structure are cleared, and associated internal codec setup data is freed.
+ * \param c A theora_info struct to initialize.
+ */
+extern void theora_info_clear(theora_info *c);
+
+/**
+ * Free all internal data associated with a theora_state handle.
+ * \param t A theora_state handle.
+ */
+extern void theora_clear(theora_state *t);
+
+/**
+ * Initialize an allocated theora_comment structure
+ * \param tc An allocated theora_comment structure
+ **/
+extern void theora_comment_init(theora_comment *tc);
+
+/**
+ * Add a comment to an initialized theora_comment structure
+ * \param tc A previously initialized theora comment structure
+ * \param comment A null-terminated string encoding the comment in the form
+ *                "TAG=the value"
+ *
+ * Neither theora_comment_add() nor theora_comment_add_tag() support
+ * comments containing null values, although the bitstream format
+ * supports this. To add such comments you will need to manipulate
+ * the theora_comment structure directly.
+ **/
+
+extern void theora_comment_add(theora_comment *tc, char *comment);
+
+/**
+ * Add a comment to an initialized theora_comment structure.
+ * \param tc A previously initialized theora comment structure
+ * \param tag A null-terminated string containing the tag
+ *            associated with the comment.
+ * \param value The corresponding value as a null-terminated string
+ *
+ * Neither theora_comment_add() nor theora_comment_add_tag() support
+ * comments containing null values, although the bitstream format
+ * supports this. To add such comments you will need to manipulate
+ * the theora_comment structure directly.
+ **/
+extern void theora_comment_add_tag(theora_comment *tc,
+                                       char *tag, char *value);
+
+/**
+ * Look up a comment value by tag.
+ * \param tc Tn initialized theora_comment structure
+ * \param tag The tag to look up
+ * \param count The instance of the tag. The same tag can appear multiple
+ *              times, each with a distinct and ordered value, so an index
+ *              is required to retrieve them all.
+ * \returns A pointer to the queried tag's value
+ * \retval NULL No matching tag is found
+ *
+ * \note Use theora_comment_query_count() to get the legal range for the
+ * count parameter.
+ **/
+
+extern char *theora_comment_query(theora_comment *tc, char *tag, int count);
+
+/** Look up the number of instances of a tag.
+ *  \param tc An initialized theora_comment structure
+ *  \param tag The tag to look up
+ *  \returns The number on instances of a particular tag.
+ *
+ *  Call this first when querying for a specific tag and then interate
+ *  over the number of instances with separate calls to
+ *  theora_comment_query() to retrieve all instances in order.
+ **/
+extern int   theora_comment_query_count(theora_comment *tc, char *tag);
+
+/**
+ * Clear an allocated theora_comment struct so that it can be freed.
+ * \param tc An allocated theora_comment structure.
+ **/
+extern void  theora_comment_clear(theora_comment *tc);
+
+/**Encoder control function.
+ * This is used to provide advanced control the encoding process.
+ * \param th     A #theora_state handle.
+ * \param req    The control code to process.
+ *                See \ref encctlcodes_old "the list of available
+ *			control codes" for details.
+ * \param buf    The parameters for this control code.
+ * \param buf_sz The size of the parameter buffer.*/
+extern int theora_control(theora_state *th,int req,void *buf,size_t buf_sz);
+
+/* @} */ /* end oldfuncs doxygen group */
+
+#ifdef __cplusplus
+}
+#endif /* __cplusplus */
+
+#endif /* _O_THEORA_H_ */