X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=mp4.h;h=c36a1f81db84bbe8c0f6a800f74a75f36cc2d93b;hb=HEAD;hp=216a6c041f5139367701b177ec6578a8187f0a1d;hpb=66491ab8498a5b57930fae018d0022579c2c17bb;p=paraslash.git diff --git a/mp4.h b/mp4.h index 216a6c04..c36a1f81 100644 --- a/mp4.h +++ b/mp4.h @@ -1,117 +1,87 @@ -struct mp4ff_callback { - uint32_t (*read)(void *user_data, void *buffer, uint32_t length); - uint32_t (*write)(void *udata, void *buffer, uint32_t length); - uint32_t (*seek)(void *user_data, uint64_t position); - uint32_t (*truncate)(void *user_data); - void *user_data; - uint32_t read_error; +/** \file mp4.h Public API of the mp4 parser. */ + +/** + * Callbacks provided by the user of the mp4 parsing API. + * + * A pointer to this structure is passed to the two public open functions. If + * the file is opened in read-only mode, the ->write() and ->truncate() methods + * won't be called and may thus be NULL. The ->read() and ->seek() methods + * must be supplied for either open type. + * + * All methods are supposed to work like their corresponding system calls. + * That is, they should return non-negative for success and -1 on failure. In + * the error case errno is expected to be set accordingly. + * + * \sa \ref mp4_open(), \ref mp4_open_meta(). + */ +struct mp4_callback { + /** This pointer is propagated to each call of all methods. */ + void *user_data; + /** + * This should return the number of bytes read on success. Short reads + * are OK: the function may return less than length. + */ + ssize_t (*read)(void *user_data, void *buffer, size_t length); + /** + * This method is assumed to succeed. The implementation should simply + * abort on errors. Note that offsets beyond EOF must not be regarded + * as invalid arguments. + */ + off_t (*seek)(void *user_data, off_t offset, int whence); + /** + * Like the write() system call, this should return the number of bytes + * written. Short writes are OK: the function may return less than + * count. + */ + ssize_t (*write)(void *user_data, void *buffer, size_t count); + /** + * Unlike the truncate system call, this function does not receive an + * offset. The method is expected to truncate the file to the offset + * given by the current file position instead. + */ + int (*truncate)(void *user_data); }; -struct mp4ff_track { - int32_t type; - int32_t channelCount; - int32_t sampleSize; - uint16_t sampleRate; - int32_t audioType; - - /* stsd */ - int32_t stsd_entry_count; - - /* stsz */ - int32_t stsz_sample_size; - int32_t stsz_sample_count; - int32_t *stsz_table; - - /* stts */ - int32_t stts_entry_count; - int32_t *stts_sample_count; - int32_t *stts_sample_delta; - - /* stsc */ - int32_t stsc_entry_count; - int32_t *stsc_first_chunk; - int32_t *stsc_samples_per_chunk; - int32_t *stsc_sample_desc_index; - - /* stsc */ - int32_t stco_entry_count; - int32_t *stco_chunk_offset; - - /* ctts */ - int32_t ctts_entry_count; - int32_t *ctts_sample_count; - int32_t *ctts_sample_offset; - - /* esde */ - uint8_t *decoderConfig; - int32_t decoderConfigLen; - - uint32_t maxBitrate; - uint32_t avgBitrate; - - uint32_t timeScale; - uint64_t duration; - -}; - -#define MAX_TRACKS 1024 - -struct mp4ff_tag { - char *item; - char *value; - uint32_t len; +/** Specifies one metadata tag. Both fields are 0-terminated strings. */ +struct mp4_tag { + /** The item name: "artist", "title", "album", "comment", or "date". */ + char *item; + /** An arbitrary string value. */ + char *value; }; -struct mp4ff_metadata { - struct mp4ff_tag *tags; - uint32_t count; +/** + * An array of name/value pairs. + * + * This structure is initialized when the mp4 file is opened in either mode. + * If the file contains metadata items other than the standard five, those + * non-standard items are not included in the array. After a successful open, a + * pointer to the metadata structure can be obtained via \ref mp4_get_meta(). + */ +struct mp4_metadata { + /** It's OK to change this, for example by calling realloc(). */ + struct mp4_tag *tags; + /** The number of entries of the array. */ + unsigned count; }; -/* mp4 main file structure */ -struct mp4ff { - /* stream to read from */ - struct mp4ff_callback *stream; - int64_t current_position; - - uint64_t moov_offset; - uint64_t moov_size; - uint8_t last_atom; - uint64_t file_size; - uint32_t error; - - /* mvhd */ - int32_t time_scale; - int32_t duration; - - /* incremental track index while reading the file */ - int32_t total_tracks; - - /* track data */ - struct mp4ff_track *track[MAX_TRACKS]; - - /* metadata */ - struct mp4ff_metadata tags; -}; - -void mp4ff_set_sample_position(struct mp4ff *f, const int32_t track, const int32_t sample); -int32_t mp4ff_total_tracks(const struct mp4ff *f); -void mp4ff_get_decoder_config(const struct mp4ff *f, const int track, - unsigned char** ppBuf, unsigned int* pBufSize); -struct mp4ff *mp4ff_open_read(struct mp4ff_callback *f); -void mp4ff_close(struct mp4ff *f); -int32_t mp4ff_get_sample_size(const struct mp4ff *f, int track, int sample); -uint32_t mp4ff_get_sample_rate(const struct mp4ff *f, const int32_t track); -uint32_t mp4ff_get_channel_count(const struct mp4ff * f,const int32_t track); -int32_t mp4ff_num_samples(const struct mp4ff *f, const int track); -struct mp4ff *mp4ff_open_read_metaonly(struct mp4ff_callback *f); - -int mp4ff_meta_get_by_index(const struct mp4ff *f, unsigned int index, - char **item, char **value); -int32_t mp4ff_meta_update(struct mp4ff_callback *f,const struct mp4ff_metadata * data); - -int mp4ff_meta_get_num_items(const struct mp4ff *f); -int mp4ff_meta_get_artist(const struct mp4ff *f, char **value); -int mp4ff_meta_get_title(const struct mp4ff *f, char **value); -int mp4ff_meta_get_date(const struct mp4ff *f, char **value); -int mp4ff_meta_get_album(const struct mp4ff *f, char **value); -int mp4ff_meta_get_comment(const struct mp4ff *f, char **value); +/** + * The mp4 file handle. + * + * A pointer to this opaque structure is returned by the two open functions. + * All other functions of the mp4 API receive a pointer of this type. + */ +struct mp4; + +int mp4_set_sample_position(struct mp4 *f, uint32_t sample); +int mp4_open(const struct mp4_callback *cb, struct mp4 **result); +void mp4_close(struct mp4 *f); +int mp4_get_sample_size(const struct mp4 *f, uint32_t sample, uint32_t *result); +uint16_t mp4_get_sample_rate(const struct mp4 *f); +uint16_t mp4_get_channel_count(const struct mp4 *f); +uint32_t mp4_num_samples(const struct mp4 *f); +uint64_t mp4_get_duration(const struct mp4 *f); +int mp4_open_meta(const struct mp4_callback *cb, struct mp4 **result); +struct mp4_metadata *mp4_get_meta(struct mp4 *f); +int mp4_update_meta(struct mp4 *f); +__malloc char *mp4_get_tag_value(const struct mp4 *f, const char *item);