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-rw-r--r--media/libnestegg/include/moz.build10
-rw-r--r--media/libnestegg/include/nestegg/nestegg.h508
2 files changed, 518 insertions, 0 deletions
diff --git a/media/libnestegg/include/moz.build b/media/libnestegg/include/moz.build
new file mode 100644
index 0000000000..07e672aa86
--- /dev/null
+++ b/media/libnestegg/include/moz.build
@@ -0,0 +1,10 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+EXPORTS.nestegg += [
+ 'nestegg/nestegg.h',
+]
+
diff --git a/media/libnestegg/include/nestegg/nestegg.h b/media/libnestegg/include/nestegg/nestegg.h
new file mode 100644
index 0000000000..dc035e9d4a
--- /dev/null
+++ b/media/libnestegg/include/nestegg/nestegg.h
@@ -0,0 +1,508 @@
+/*
+ * Copyright © 2010 Mozilla Foundation
+ *
+ * This program is made available under an ISC-style license. See the
+ * accompanying file LICENSE for details.
+ */
+#if !defined(NESTEGG_671cac2a_365d_ed69_d7a3_4491d3538d79)
+#define NESTEGG_671cac2a_365d_ed69_d7a3_4491d3538d79
+
+#include <limits.h>
+#include <stdint.h>
+
+#if defined(__cplusplus)
+extern "C" {
+#endif
+
+/** @mainpage
+
+ @section intro Introduction
+
+ This is the documentation for the <tt>libnestegg</tt> C API.
+ <tt>libnestegg</tt> is a demultiplexing library for <a
+ href="http://www.webmproject.org/code/specs/container/">WebM</a>
+ media files.
+
+ @section example Example code
+
+ @code
+ nestegg * demux_ctx;
+ nestegg_init(&demux_ctx, io, NULL, -1);
+
+ nestegg_packet * pkt;
+ while ((r = nestegg_read_packet(demux_ctx, &pkt)) > 0) {
+ unsigned int track;
+
+ nestegg_packet_track(pkt, &track);
+
+ // This example decodes the first track only.
+ if (track == 0) {
+ unsigned int chunk, chunks;
+
+ nestegg_packet_count(pkt, &chunks);
+
+ // Decode each chunk of data.
+ for (chunk = 0; chunk < chunks; ++chunk) {
+ unsigned char * data;
+ size_t data_size;
+
+ nestegg_packet_data(pkt, chunk, &data, &data_size);
+
+ example_codec_decode(codec_ctx, data, data_size);
+ }
+ }
+
+ nestegg_free_packet(pkt);
+ }
+
+ nestegg_destroy(demux_ctx);
+ @endcode
+*/
+
+
+/** @file
+ The <tt>libnestegg</tt> C API. */
+
+#define NESTEGG_TRACK_VIDEO 0 /**< Track is of type video. */
+#define NESTEGG_TRACK_AUDIO 1 /**< Track is of type audio. */
+#define NESTEGG_TRACK_UNKNOWN INT_MAX /**< Track is of type unknown. */
+
+#define NESTEGG_CODEC_VP8 0 /**< Track uses Google On2 VP8 codec. */
+#define NESTEGG_CODEC_VORBIS 1 /**< Track uses Xiph Vorbis codec. */
+#define NESTEGG_CODEC_VP9 2 /**< Track uses Google On2 VP9 codec. */
+#define NESTEGG_CODEC_OPUS 3 /**< Track uses Xiph Opus codec. */
+#define NESTEGG_CODEC_AV1 4 /**< Track uses AOMedia AV1 codec. */
+#define NESTEGG_CODEC_UNKNOWN INT_MAX /**< Track uses unknown codec. */
+
+#define NESTEGG_VIDEO_MONO 0 /**< Track is mono video. */
+#define NESTEGG_VIDEO_STEREO_LEFT_RIGHT 1 /**< Track is side-by-side stereo video. Left first. */
+#define NESTEGG_VIDEO_STEREO_BOTTOM_TOP 2 /**< Track is top-bottom stereo video. Right first. */
+#define NESTEGG_VIDEO_STEREO_TOP_BOTTOM 3 /**< Track is top-bottom stereo video. Left first. */
+#define NESTEGG_VIDEO_STEREO_RIGHT_LEFT 11 /**< Track is side-by-side stereo video. Right first. */
+
+#define NESTEGG_SEEK_SET 0 /**< Seek offset relative to beginning of stream. */
+#define NESTEGG_SEEK_CUR 1 /**< Seek offset relative to current position in stream. */
+#define NESTEGG_SEEK_END 2 /**< Seek offset relative to end of stream. */
+
+#define NESTEGG_LOG_DEBUG 1 /**< Debug level log message. */
+#define NESTEGG_LOG_INFO 10 /**< Informational level log message. */
+#define NESTEGG_LOG_WARNING 100 /**< Warning level log message. */
+#define NESTEGG_LOG_ERROR 1000 /**< Error level log message. */
+#define NESTEGG_LOG_CRITICAL 10000 /**< Critical level log message. */
+
+#define NESTEGG_ENCODING_COMPRESSION 0 /**< Content encoding type is compression. */
+#define NESTEGG_ENCODING_ENCRYPTION 1 /**< Content encoding type is encryption. */
+
+#define NESTEGG_PACKET_HAS_SIGNAL_BYTE_FALSE 0 /**< Packet does not have signal byte */
+#define NESTEGG_PACKET_HAS_SIGNAL_BYTE_UNENCRYPTED 1 /**< Packet has signal byte and is unencrypted */
+#define NESTEGG_PACKET_HAS_SIGNAL_BYTE_ENCRYPTED 2 /**< Packet has signal byte and is encrypted */
+#define NESTEGG_PACKET_HAS_SIGNAL_BYTE_PARTITIONED 4 /**< Packet has signal byte and is partitioned */
+
+#define NESTEGG_PACKET_HAS_KEYFRAME_FALSE 0 /**< Packet contains only keyframes. */
+#define NESTEGG_PACKET_HAS_KEYFRAME_TRUE 1 /**< Packet does not contain any keyframes */
+#define NESTEGG_PACKET_HAS_KEYFRAME_UNKNOWN 2 /**< Packet may or may not contain keyframes */
+
+typedef struct nestegg nestegg; /**< Opaque handle referencing the stream state. */
+typedef struct nestegg_packet nestegg_packet; /**< Opaque handle referencing a packet of data. */
+
+/** User supplied IO context. */
+typedef struct {
+ /** User supplied read callback.
+ @param buffer Buffer to read data into.
+ @param length Length of supplied buffer in bytes.
+ @param userdata The #userdata supplied by the user.
+ @retval 1 Read succeeded.
+ @retval 0 End of stream.
+ @retval -1 Error. */
+ int (* read)(void * buffer, size_t length, void * userdata);
+
+ /** User supplied seek callback.
+ @param offset Offset within the stream to seek to.
+ @param whence Seek direction. One of #NESTEGG_SEEK_SET,
+ #NESTEGG_SEEK_CUR, or #NESTEGG_SEEK_END.
+ @param userdata The #userdata supplied by the user.
+ @retval 0 Seek succeeded.
+ @retval -1 Error. */
+ int (* seek)(int64_t offset, int whence, void * userdata);
+
+ /** User supplied tell callback.
+ @param userdata The #userdata supplied by the user.
+ @returns Current position within the stream.
+ @retval -1 Error. */
+ int64_t (* tell)(void * userdata);
+
+ /** User supplied pointer to be passed to the IO callbacks. */
+ void * userdata;
+} nestegg_io;
+
+/** Parameters specific to a video track. */
+typedef struct {
+ unsigned int stereo_mode; /**< Video mode. One of #NESTEGG_VIDEO_MONO,
+ #NESTEGG_VIDEO_STEREO_LEFT_RIGHT,
+ #NESTEGG_VIDEO_STEREO_BOTTOM_TOP, or
+ #NESTEGG_VIDEO_STEREO_TOP_BOTTOM. */
+ unsigned int width; /**< Width of the video frame in pixels. */
+ unsigned int height; /**< Height of the video frame in pixels. */
+ unsigned int display_width; /**< Display width of the video frame in pixels. */
+ unsigned int display_height; /**< Display height of the video frame in pixels. */
+ unsigned int crop_bottom; /**< Pixels to crop from the bottom of the frame. */
+ unsigned int crop_top; /**< Pixels to crop from the top of the frame. */
+ unsigned int crop_left; /**< Pixels to crop from the left of the frame. */
+ unsigned int crop_right; /**< Pixels to crop from the right of the frame. */
+ unsigned int alpha_mode; /**< 1 if an additional opacity stream is available, otherwise 0. */
+ unsigned int matrix_coefficients; /**< See Table 4 of ISO/IEC 23001-8:2016. */
+ unsigned int range; /**< Clipping of color ranges. */
+ unsigned int transfer_characteristics; /**< See Table 3 of ISO/IEC 23091-4. */
+ unsigned int primaries; /**< See Table 2 of ISO/IEC 23091-4. */
+ double primary_r_chromacity_x; /**< Red X chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double primary_r_chromacity_y; /**< Red Y chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double primary_g_chromacity_x; /**< Green X chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double primary_g_chromacity_y; /**< Green Y chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double primary_b_chromacity_x; /**< Blue X chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double primary_b_chromacity_y; /**< Blue Y chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double white_point_chromaticity_x; /**< White X chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double white_point_chromaticity_y; /**< White Y chromaticity coordinate per CIE 1931.
+ NaN means element not present. */
+ double luminance_max; /**< Maximum luminance in cd/m2.
+ NaN means element not present. */
+ double luminance_min; /**< Minimum luminance in cd/m2.
+ NaN means element not present. */
+} nestegg_video_params;
+
+/** Parameters specific to an audio track. */
+typedef struct {
+ double rate; /**< Sampling rate in Hz. */
+ unsigned int channels; /**< Number of audio channels. */
+ unsigned int depth; /**< Bits per sample. */
+ uint64_t codec_delay; /**< Nanoseconds that must be discarded from the start. */
+ uint64_t seek_preroll;/**< Nanoseconds that must be discarded after a seek. */
+} nestegg_audio_params;
+
+/** Logging callback function pointer. */
+typedef void (* nestegg_log)(nestegg * context, unsigned int severity, char const * format, ...);
+
+/** Initialize a nestegg context. During initialization the parser will
+ read forward in the stream processing all elements until the first
+ block of media is reached. All track metadata has been processed at this point.
+ @param context Storage for the new nestegg context. @see nestegg_destroy
+ @param io User supplied IO context.
+ @param callback Optional logging callback function pointer. May be NULL.
+ @param max_offset Optional maximum offset to be read. Set -1 to ignore.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_init(nestegg ** context, nestegg_io io, nestegg_log callback, int64_t max_offset);
+
+/** Destroy a nestegg context and free associated memory.
+ @param context #nestegg context to be freed. @see nestegg_init */
+void nestegg_destroy(nestegg * context);
+
+/** Query the duration of the media stream in nanoseconds.
+ @param context Stream context initialized by #nestegg_init.
+ @param duration Storage for the queried duration.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_duration(nestegg * context, uint64_t * duration);
+
+/** Query the tstamp scale of the media stream in nanoseconds.
+ @note Timestamps presented by nestegg have been scaled by this value
+ before presentation to the caller.
+ @param context Stream context initialized by #nestegg_init.
+ @param scale Storage for the queried scale factor.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_tstamp_scale(nestegg * context, uint64_t * scale);
+
+/** Query the number of tracks in the media stream.
+ @param context Stream context initialized by #nestegg_init.
+ @param tracks Storage for the queried track count.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_count(nestegg * context, unsigned int * tracks);
+
+/** Query the start and end offset for a particular cluster.
+ @param context Stream context initialized by #nestegg_init.
+ @param cluster_num Zero-based cluster number; order they appear in cues.
+ @param max_offset Optional maximum offset to be read. Set -1 to ignore.
+ @param start_pos Starting offset of the cluster. -1 means non-existant.
+ @param end_pos Starting offset of the cluster. -1 means non-existant or
+ final cluster.
+ @param tstamp Starting timestamp of the cluster.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_get_cue_point(nestegg * context, unsigned int cluster_num,
+ int64_t max_offset, int64_t * start_pos,
+ int64_t * end_pos, uint64_t * tstamp);
+
+/** Seek to @a offset. Stream will seek directly to offset.
+ Must be used to seek to the start of a cluster; the parser will not be
+ able to understand other offsets.
+ @param context Stream context initialized by #nestegg_init.
+ @param offset Absolute offset in bytes.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_offset_seek(nestegg * context, uint64_t offset);
+
+/** Seek @a track to @a tstamp. Stream seek will terminate at the earliest
+ key point in the stream at or before @a tstamp. Other tracks in the
+ stream will output packets with unspecified but nearby timestamps.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param tstamp Absolute timestamp in nanoseconds.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_seek(nestegg * context, unsigned int track, uint64_t tstamp);
+
+/** Query the type specified by @a track.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @retval #NESTEGG_TRACK_VIDEO Track type is video.
+ @retval #NESTEGG_TRACK_AUDIO Track type is audio.
+ @retval #NESTEGG_TRACK_UNKNOWN Track type is unknown.
+ @retval -1 Error. */
+int nestegg_track_type(nestegg * context, unsigned int track);
+
+/** Query the codec ID specified by @a track.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @retval #NESTEGG_CODEC_VP8 Track codec is VP8.
+ @retval #NESTEGG_CODEC_VP9 Track codec is VP9.
+ @retval #NESTEGG_CODEC_AV1 Track codec is AV1.
+ @retval #NESTEGG_CODEC_VORBIS Track codec is Vorbis.
+ @retval #NESTEGG_CODEC_OPUS Track codec is Opus.
+ @retval #NESTEGG_CODEC_UNKNOWN Track codec is unknown.
+ @retval -1 Error. */
+int nestegg_track_codec_id(nestegg * context, unsigned int track);
+
+/** Query the number of codec initialization chunks for @a track. Each
+ chunk of data should be passed to the codec initialization functions in
+ the order returned.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param count Storage for the queried chunk count.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_codec_data_count(nestegg * context, unsigned int track,
+ unsigned int * count);
+
+/** Get a pointer to chunk number @a item of codec initialization data for
+ @a track.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param item Zero based chunk item number.
+ @param data Storage for the queried data pointer.
+ The data is owned by the #nestegg context.
+ @param length Storage for the queried data size.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_codec_data(nestegg * context, unsigned int track, unsigned int item,
+ unsigned char ** data, size_t * length);
+
+/** Query the video parameters specified by @a track.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param params Storage for the queried video parameters.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_video_params(nestegg * context, unsigned int track,
+ nestegg_video_params * params);
+
+/** Query the audio parameters specified by @a track.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param params Storage for the queried audio parameters.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_audio_params(nestegg * context, unsigned int track,
+ nestegg_audio_params * params);
+
+/** Query the encoding status for @a track. If a track has multiple encodings
+ the first will be returned.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @retval #NESTEGG_ENCODING_COMPRESSION The track is compressed, but not encrypted.
+ @retval #NESTEGG_ENCODING_ENCRYPTION The track is encrypted and compressed.
+ @retval -1 Error. */
+int nestegg_track_encoding(nestegg * context, unsigned int track);
+
+/** Query the ContentEncKeyId for @a track. Will return an error if the track
+ in not encrypted, or is not recognized.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param content_enc_key_id Storage for queried id. The content encryption key used.
+ Owned by nestegg and will be freed separately.
+ @param content_enc_key_id_length Length of the queried ContentEncKeyId in bytes.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_content_enc_key_id(nestegg * context, unsigned int track,
+ unsigned char const ** content_enc_key_id,
+ size_t * content_enc_key_id_length);
+
+/** Query the default frame duration for @a track. For a video track, this
+ is typically the inverse of the video frame rate.
+ @param context Stream context initialized by #nestegg_init.
+ @param track Zero based track number.
+ @param duration Storage for the default duration in nanoseconds.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_track_default_duration(nestegg * context, unsigned int track,
+ uint64_t * duration);
+
+/** Reset parser state to the last valid state before nestegg_read_packet failed.
+ @param context Stream context initialized by #nestegg_init.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_read_reset(nestegg * context);
+
+/** Read a packet of media data. A packet consists of one or more chunks of
+ data associated with a single track. nestegg_read_packet should be
+ called in a loop while the return value is 1 to drive the stream parser
+ forward. @see nestegg_free_packet
+ @param context Context returned by #nestegg_init.
+ @param packet Storage for the returned nestegg_packet.
+ @retval 1 Additional packets may be read in subsequent calls.
+ @retval 0 End of stream.
+ @retval -1 Error. */
+int nestegg_read_packet(nestegg * context, nestegg_packet ** packet);
+
+/** Destroy a nestegg_packet and free associated memory.
+ @param packet #nestegg_packet to be freed. @see nestegg_read_packet */
+void nestegg_free_packet(nestegg_packet * packet);
+
+/** Query the keyframe status for a given packet.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @retval #NESTEGG_PACKET_HAS_KEYFRAME_FALSE Packet contains no keyframes.
+ @retval #NESTEGG_PACKET_HAS_KEYFRAME_TRUE Packet contains keyframes.
+ @retval #NESTEGG_PACKET_HAS_KEYFRAME_UNKNOWN Unknown packet keyframe content.
+ @retval -1 Error. */
+int nestegg_packet_has_keyframe(nestegg_packet * packet);
+
+/** Query the track number of @a packet.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param track Storage for the queried zero based track index.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_track(nestegg_packet * packet, unsigned int * track);
+
+/** Query the timestamp in nanoseconds of @a packet.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param tstamp Storage for the queried timestamp in nanoseconds.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_tstamp(nestegg_packet * packet, uint64_t * tstamp);
+
+/** Query the duration in nanoseconds of @a packet.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param duration Storage for the queried duration in nanoseconds.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_duration(nestegg_packet * packet, uint64_t * duration);
+
+/** Query the number of data chunks contained in @a packet.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param count Storage for the queried chunk count.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_count(nestegg_packet * packet, unsigned int * count);
+
+/** Get a pointer to chunk number @a item of packet data.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param item Zero based chunk item number.
+ @param data Storage for the queried data pointer.
+ The data is owned by the #nestegg_packet packet.
+ @param length Storage for the queried data size.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_data(nestegg_packet * packet, unsigned int item,
+ unsigned char ** data, size_t * length);
+
+/** Get a pointer to additional data with identifier @a id of additional packet
+ data. If @a id isn't present in the packet, returns -1.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param id Codec specific identifer. For VP8, use 1 to get a VP8 encoded
+ frame containing an alpha channel in its Y plane.
+ @param data Storage for the queried data pointer.
+ The data is owned by the #nestegg_packet packet.
+ @param length Storage for the queried data size.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_additional_data(nestegg_packet * packet, unsigned int id,
+ unsigned char ** data, size_t * length);
+
+/** Returns discard_padding for given packet
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param discard_padding pointer to store discard padding in.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_discard_padding(nestegg_packet * packet,
+ int64_t * discard_padding);
+
+/** Query if a packet is encrypted.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @retval #NESTEGG_PACKET_HAS_SIGNAL_BYTE_FALSE No signal byte, encryption
+ information not read from packet.
+ @retval #NESTEGG_PACKET_HAS_SIGNAL_BYTE_UNENCRYPTED Encrypted bit not
+ set, encryption information not read from packet.
+ @retval #NESTEGG_PACKET_HAS_SIGNAL_BYTE_ENCRYPTED Encrypted bit set,
+ encryption infomation read from packet.
+ @retval #NESTEGG_PACKET_HAS_SIGNAL_BYTE_PARTITIONED Partitioned bit set,
+ encryption and parition information read from packet.
+ @retval -1 Error.*/
+int nestegg_packet_encryption(nestegg_packet * packet);
+
+/** Query the IV for an encrypted packet. Expects a packet from an encrypted
+ track, and will return error if given a packet that has no signal btye.
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param iv Storage for queried iv.
+ @param length Length of returned iv, may be 0.
+ The data is owned by the #nestegg_packet packet.
+ @retval 0 Success.
+ @retval -1 Error.
+ */
+int nestegg_packet_iv(nestegg_packet * packet, unsigned char const ** iv,
+ size_t * length);
+
+/** Query the packet for offsets.
+@param packet Packet initialized by #nestegg_read_packet.
+@param partition_offsets Storage for queried offsets.
+@param num_offsets Length of returned offsets, may be 0.
+The data is owned by the #nestegg_packet packet.
+@retval 0 Success.
+@retval -1 Error.
+*/
+int nestegg_packet_offsets(nestegg_packet * packet,
+ uint32_t const ** partition_offsets,
+ uint8_t * num_offsets);
+
+/** Returns reference_block given packet
+ @param packet Packet initialized by #nestegg_read_packet.
+ @param reference_block pointer to store reference block in.
+ @retval 0 Success.
+ @retval -1 Error. */
+int nestegg_packet_reference_block(nestegg_packet * packet,
+ int64_t * reference_block);
+
+/** Query the presence of cues.
+ @param context Stream context initialized by #nestegg_init.
+ @retval 0 The media has no cues.
+ @retval 1 The media has cues. */
+int nestegg_has_cues(nestegg * context);
+
+/** Try to determine if the buffer looks like the beginning of a WebM file.
+ @param buffer A buffer containing the beginning of a media file.
+ @param length The size of the buffer.
+ @retval 0 The file is not a WebM file.
+ @retval 1 The file is a WebM file. */
+int nestegg_sniff(unsigned char const * buffer, size_t length);
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* NESTEGG_671cac2a_365d_ed69_d7a3_4491d3538d79 */