stream_decoder.c

这是著名的TCPMP播放器在WINDWOWS,和WINCE下编译通过的源程序.笔者对其中的LIBMAD库做了针对ARM MPU的优化. 并增加了词幕功能.

			if(decoder->private_->metadata_filter_ids_count > 0 && has_id_filtered_(decoder, block.data.application.id))
				skip_it = !skip_it;
		}

		if(skip_it) {
			if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, 0, real_length, read_callback_, decoder))
				return false; /* the read_callback_ sets the state for us */
		}
		else {
			switch(type) {
				case FLAC__METADATA_TYPE_PADDING:
					/* skip the padding bytes */
					if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, 0, real_length, read_callback_, decoder))
						return false; /* the read_callback_ sets the state for us */
					break;
				case FLAC__METADATA_TYPE_APPLICATION:
					/* remember, we read the ID already */
					if(real_length > 0) {
						if(0 == (block.data.application.data = (FLAC__byte*)malloc(real_length))) {
							decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
							return false;
						}
						if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.application.data, real_length, read_callback_, decoder))
							return false; /* the read_callback_ sets the state for us */
					}
					else
						block.data.application.data = 0;
					break;
				case FLAC__METADATA_TYPE_VORBIS_COMMENT:
					if(!read_metadata_vorbiscomment_(decoder, &block.data.vorbis_comment))
						return false;
					break;
				case FLAC__METADATA_TYPE_CUESHEET:
					if(!read_metadata_cuesheet_(decoder, &block.data.cue_sheet))
						return false;
					break;
				case FLAC__METADATA_TYPE_STREAMINFO:
				case FLAC__METADATA_TYPE_SEEKTABLE:
					FLAC__ASSERT(0);
					break;
				default:
					if(real_length > 0) {
						if(0 == (block.data.unknown.data = (FLAC__byte*)malloc(real_length))) {
							decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
							return false;
						}
						if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, block.data.unknown.data, real_length, read_callback_, decoder))
							return false; /* the read_callback_ sets the state for us */
					}
					else
						block.data.unknown.data = 0;
					break;
			}
			decoder->private_->metadata_callback(decoder, &block, decoder->private_->client_data);

			/* now we have to free any malloc'ed data in the block */
			switch(type) {
				case FLAC__METADATA_TYPE_PADDING:
					break;
				case FLAC__METADATA_TYPE_APPLICATION:
					if(0 != block.data.application.data)
						free(block.data.application.data);
					break;
				case FLAC__METADATA_TYPE_VORBIS_COMMENT:
					if(0 != block.data.vorbis_comment.vendor_string.entry)
						free(block.data.vorbis_comment.vendor_string.entry);
					if(block.data.vorbis_comment.num_comments > 0)
						for(i = 0; i < block.data.vorbis_comment.num_comments; i++)
							if(0 != block.data.vorbis_comment.comments[i].entry)
								free(block.data.vorbis_comment.comments[i].entry);
					if(0 != block.data.vorbis_comment.comments)
						free(block.data.vorbis_comment.comments);
					break;
				case FLAC__METADATA_TYPE_CUESHEET:
					if(block.data.cue_sheet.num_tracks > 0)
						for(i = 0; i < block.data.cue_sheet.num_tracks; i++)
							if(0 != block.data.cue_sheet.tracks[i].indices)
								free(block.data.cue_sheet.tracks[i].indices);
					if(0 != block.data.cue_sheet.tracks)
						free(block.data.cue_sheet.tracks);
					break;
				case FLAC__METADATA_TYPE_STREAMINFO:
				case FLAC__METADATA_TYPE_SEEKTABLE:
					FLAC__ASSERT(0);
				default:
					if(0 != block.data.unknown.data)
						free(block.data.unknown.data);
					break;
			}
		}
	}

	if(is_last)
		decoder->protected_->state = FLAC__STREAM_DECODER_SEARCH_FOR_FRAME_SYNC;

	return true;
}

FLAC__bool read_metadata_streaminfo_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
{
	FLAC__uint32 x;
	unsigned bits, used_bits = 0;

	FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));

	decoder->private_->stream_info.type = FLAC__METADATA_TYPE_STREAMINFO;
	decoder->private_->stream_info.is_last = is_last;
	decoder->private_->stream_info.length = length;

	bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_BLOCK_SIZE_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, bits, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.min_blocksize = x;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_BLOCK_SIZE_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.max_blocksize = x;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MIN_FRAME_SIZE_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.min_framesize = x;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_MAX_FRAME_SIZE_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.max_framesize = x;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_SAMPLE_RATE_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.sample_rate = x;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_CHANNELS_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.channels = x+1;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN;
	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_STREAMINFO_BITS_PER_SAMPLE_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	decoder->private_->stream_info.data.stream_info.bits_per_sample = x+1;
	used_bits += bits;

	bits = FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN;
	if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &decoder->private_->stream_info.data.stream_info.total_samples, FLAC__STREAM_METADATA_STREAMINFO_TOTAL_SAMPLES_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	used_bits += bits;

	if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, decoder->private_->stream_info.data.stream_info.md5sum, 16, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	used_bits += 16*8;

	/* skip the rest of the block */
	FLAC__ASSERT(used_bits % 8 == 0);
	length -= (used_bits / 8);
	if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, 0, length, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */

	return true;
}

FLAC__bool read_metadata_seektable_(FLAC__StreamDecoder *decoder, FLAC__bool is_last, unsigned length)
{
	FLAC__uint32 i, x;
	FLAC__uint64 xx;

	FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));

	decoder->private_->seek_table.type = FLAC__METADATA_TYPE_SEEKTABLE;
	decoder->private_->seek_table.is_last = is_last;
	decoder->private_->seek_table.length = length;

	decoder->private_->seek_table.data.seek_table.num_points = length / FLAC__STREAM_METADATA_SEEKPOINT_LENGTH;

	/* use realloc since we may pass through here several times (e.g. after seeking) */
	if(0 == (decoder->private_->seek_table.data.seek_table.points = (FLAC__StreamMetadata_SeekPoint*)realloc(decoder->private_->seek_table.data.seek_table.points, decoder->private_->seek_table.data.seek_table.num_points * sizeof(FLAC__StreamMetadata_SeekPoint)))) {
		decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
		return false;
	}
	for(i = 0; i < decoder->private_->seek_table.data.seek_table.num_points; i++) {
		if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_SAMPLE_NUMBER_LEN, read_callback_, decoder))
			return false; /* the read_callback_ sets the state for us */
		decoder->private_->seek_table.data.seek_table.points[i].sample_number = xx;

		if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &xx, FLAC__STREAM_METADATA_SEEKPOINT_STREAM_OFFSET_LEN, read_callback_, decoder))
			return false; /* the read_callback_ sets the state for us */
		decoder->private_->seek_table.data.seek_table.points[i].stream_offset = xx;

		if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_SEEKPOINT_FRAME_SAMPLES_LEN, read_callback_, decoder))
			return false; /* the read_callback_ sets the state for us */
		decoder->private_->seek_table.data.seek_table.points[i].frame_samples = x;
	}
	length -= (decoder->private_->seek_table.data.seek_table.num_points * FLAC__STREAM_METADATA_SEEKPOINT_LENGTH);
	/* if there is a partial point left, skip over it */
	if(length > 0) {
		/*@@@ do an error_callback() here?  there's an argument for either way */
		if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, 0, length, read_callback_, decoder))
			return false; /* the read_callback_ sets the state for us */
	}

	return true;
}

FLAC__bool read_metadata_vorbiscomment_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_VorbisComment *obj)
{
	FLAC__uint32 i;

	FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));

	/* read vendor string */
	FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
	if(!FLAC__bitbuffer_read_raw_uint32_little_endian(decoder->private_->input, &obj->vendor_string.length, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	if(obj->vendor_string.length > 0) {
		if(0 == (obj->vendor_string.entry = (FLAC__byte*)malloc(obj->vendor_string.length+1))) {
			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
			return false;
		}
		if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, obj->vendor_string.entry, obj->vendor_string.length, read_callback_, decoder))
			return false; /* the read_callback_ sets the state for us */
		obj->vendor_string.entry[obj->vendor_string.length] = '\0';
	}
	else
		obj->vendor_string.entry = 0;

	/* read num comments */
	FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_NUM_COMMENTS_LEN == 32);
	if(!FLAC__bitbuffer_read_raw_uint32_little_endian(decoder->private_->input, &obj->num_comments, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */

	/* read comments */
	if(obj->num_comments > 0) {
		if(0 == (obj->comments = (FLAC__StreamMetadata_VorbisComment_Entry*)malloc(obj->num_comments * sizeof(FLAC__StreamMetadata_VorbisComment_Entry)))) {
			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
			return false;
		}
		for(i = 0; i < obj->num_comments; i++) {
			FLAC__ASSERT(FLAC__STREAM_METADATA_VORBIS_COMMENT_ENTRY_LENGTH_LEN == 32);
			if(!FLAC__bitbuffer_read_raw_uint32_little_endian(decoder->private_->input, &obj->comments[i].length, read_callback_, decoder))
				return false; /* the read_callback_ sets the state for us */
			if(obj->comments[i].length > 0) {
				if(0 == (obj->comments[i].entry = (FLAC__byte*)malloc(obj->comments[i].length+1))) {
					decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
					return false;
				}
				if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, obj->comments[i].entry, obj->comments[i].length, read_callback_, decoder))
					return false; /* the read_callback_ sets the state for us */
				obj->comments[i].entry[obj->comments[i].length] = '\0';
			}
			else
				obj->comments[i].entry = 0;
		}
	}
	else {
		obj->comments = 0;
	}

	return true;
}

FLAC__bool read_metadata_cuesheet_(FLAC__StreamDecoder *decoder, FLAC__StreamMetadata_CueSheet *obj)
{
	FLAC__uint32 i, j, x;

	FLAC__ASSERT(FLAC__bitbuffer_is_consumed_byte_aligned(decoder->private_->input));

	memset(obj, 0, sizeof(FLAC__StreamMetadata_CueSheet));

	FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN % 8 == 0);
	if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)obj->media_catalog_number, FLAC__STREAM_METADATA_CUESHEET_MEDIA_CATALOG_NUMBER_LEN/8, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */

	if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &obj->lead_in, FLAC__STREAM_METADATA_CUESHEET_LEAD_IN_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */

	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_IS_CD_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	obj->is_cd = x? true : false;

	if(!FLAC__bitbuffer_skip_bits_no_crc(decoder->private_->input, FLAC__STREAM_METADATA_CUESHEET_RESERVED_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */

	if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_NUM_TRACKS_LEN, read_callback_, decoder))
		return false; /* the read_callback_ sets the state for us */
	obj->num_tracks = x;

	if(obj->num_tracks > 0) {
		if(0 == (obj->tracks = (FLAC__StreamMetadata_CueSheet_Track*)calloc(obj->num_tracks, sizeof(FLAC__StreamMetadata_CueSheet_Track)))) {
			decoder->protected_->state = FLAC__STREAM_DECODER_MEMORY_ALLOCATION_ERROR;
			return false;
		}
		for(i = 0; i < obj->num_tracks; i++) {
			FLAC__StreamMetadata_CueSheet_Track *track = &obj->tracks[i];
			if(!FLAC__bitbuffer_read_raw_uint64(decoder->private_->input, &track->offset, FLAC__STREAM_METADATA_CUESHEET_TRACK_OFFSET_LEN, read_callback_, decoder))
				return false; /* the read_callback_ sets the state for us */

			if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_NUMBER_LEN, read_callback_, decoder))
				return false; /* the read_callback_ sets the state for us */
			track->number = (FLAC__byte)x;

			FLAC__ASSERT(FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN % 8 == 0);
			if(!FLAC__bitbuffer_read_byte_block_aligned_no_crc(decoder->private_->input, (FLAC__byte*)track->isrc, FLAC__STREAM_METADATA_CUESHEET_TRACK_ISRC_LEN/8, read_callback_, decoder))
				return false; /* the read_callback_ sets the state for us */

			if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_TYPE_LEN, read_callback_, decoder))
				return false; /* the read_callback_ sets the state for us */
			track->type = x;

			if(!FLAC__bitbuffer_read_raw_uint32(decoder->private_->input, &x, FLAC__STREAM_METADATA_CUESHEET_TRACK_PRE_EMPHASIS_LEN, read_callback_, decoder))