Ejemplo n.º 1
0
/* parse root atoms */
static int32_t parse_atoms_int (mp4ff_t *f,int meta_only,int stop_on_mdat)
{
    uint64_t size;
    uint8_t atom_type = 0;
    uint8_t header_size = 0;
    int had_valid_atoms = 0;

    f->file_size = 0;

    while ((size = mp4ff_atom_read_header(f, &atom_type, &header_size)) != 0)
    {
        // FIXME: ATOM_UNKNOWN is returned both when a valid (but unknown) atom is encontered,
        // and for invalid data. They need to be handled separately.
        if (atom_type == ATOM_UNKNOWN && !had_valid_atoms && mp4ff_position(f)+size > 100) {
            return -1;
        }

        had_valid_atoms = 1;

        f->file_size += size;
        f->last_atom = atom_type;

        if (atom_type == ATOM_MDAT && f->moov_read)
        {
            /* moov atom is before mdat, we can stop reading when mdat is encountered */
            /* file position will stay at beginning of mdat data */
            if (!stop_on_mdat) {
                break;
            }
        }

        if (atom_type == ATOM_MOOV && size > header_size)
        {
            f->moov_read = 1;
            f->moov_offset = mp4ff_position(f)-header_size;
            f->moov_size = size;
        }

        /* parse subatoms */
		if (meta_only && !need_parse_when_meta_only(atom_type))
		{
			mp4ff_set_position(f, mp4ff_position(f)+size-header_size);
		} else if (atom_type < SUBATOMIC)
        {
            parse_sub_atoms(f, size-header_size,meta_only);
        } else {
            /* skip this atom */
            mp4ff_set_position(f, mp4ff_position(f)+size-header_size);
        }
    }

    return 0;
}
Ejemplo n.º 2
0
/* parse atoms that are sub atoms of other atoms */
int32_t parse_sub_atoms(mp4ff_t *f, const uint64_t total_size,int meta_only)
{
    uint64_t size;
    uint8_t atom_type = 0;
    uint64_t counted_size = 0;
    uint8_t header_size = 0;

    while (counted_size < total_size)
    {
        size = mp4ff_atom_read_header(f, &atom_type, &header_size);
        counted_size += size;

        /* check for end of file */
        if (size == 0)
            break;

        /* we're starting to read a new track, update index,
         * so that all data and tables get written in the right place
         */
        if (atom_type == ATOM_TRAK)
        {
            mp4ff_track_add(f);
        }

        /* parse subatoms */
		if (meta_only && !need_parse_when_meta_only(atom_type))
		{
			mp4ff_set_position(f, mp4ff_position(f)+size-header_size);
		} else if (atom_type < SUBATOMIC)
        {
            parse_sub_atoms(f, size-header_size,meta_only);
        } else {
            mp4ff_atom_read(f, (uint32_t)size, atom_type);
        }
#if 0
        if (atom_type == ATOM_TRAK)
        {
            trace ("mp4ff_track_create_chunks_index\n");
            mp4ff_track_create_chunks_index (f, f->track[f->total_tracks-1]);
            trace ("mp4ff_track_create_samples_index\n");
            mp4ff_track_create_samples_index (f, f->track[f->total_tracks-1]);
        }
#endif
    }

    return 0;
}
Ejemplo n.º 3
0
/* parse root atoms */
int32_t parse_atoms(mp4ff_t *f,int meta_only)
{
    uint64_t size;
    uint8_t atom_type = 0;
    uint8_t header_size = 0;

    f->file_size = 0;

    while ((size = mp4ff_atom_read_header(f, &atom_type, &header_size)) != 0)
    {
        f->file_size += size;
        f->last_atom = atom_type;

        if (atom_type == ATOM_MDAT && f->moov_read)
        {
            /* moov atom is before mdat, we can stop reading when mdat is encountered */
            /* file position will stay at beginning of mdat data */
//            break;
        }

        if (atom_type == ATOM_MOOV && size > header_size)
        {
            f->moov_read = 1;
            f->moov_offset = mp4ff_position(f)-header_size;
            f->moov_size = size;
        }

        /* parse subatoms */
		if (meta_only && !need_parse_when_meta_only(atom_type))
		{
			mp4ff_set_position(f, mp4ff_position(f)+size-header_size);
		} else if (atom_type < SUBATOMIC)
        {
            parse_sub_atoms(f, size-header_size,meta_only);
        } else {
            /* skip this atom */
            mp4ff_set_position(f, mp4ff_position(f)+size-header_size);
        }
    }

    return 0;
}