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| author | Andreas Huber <andih@google.com> | 2010-03-31 11:33:19 -0700 |
|---|---|---|
| committer | Android (Google) Code Review <android-gerrit@google.com> | 2010-03-31 11:33:19 -0700 |
| commit | 804878f3a3ea40ace5bd572cee98f9e13a0dbf0b (patch) | |
| tree | b695cbd17caf8ca6a218d9dfbefa264e444a9e51 /media | |
| parent | e259bc770b3eeb88eb7a03ec0af2522ca9929f58 (diff) | |
| parent | 0d34d8b4d5ad8695daef2e0db9e8316fab8942d4 (diff) | |
| download | frameworks_base-804878f3a3ea40ace5bd572cee98f9e13a0dbf0b.zip frameworks_base-804878f3a3ea40ace5bd572cee98f9e13a0dbf0b.tar.gz frameworks_base-804878f3a3ea40ace5bd572cee98f9e13a0dbf0b.tar.bz2 | |
Merge "Skip any number of leading ID3v2 tags (instead of just the first), also simplify/fix the find-consecutive-mp3-frames functionality." into froyo
Diffstat (limited to 'media')
| -rw-r--r-- | media/libstagefright/MP3Extractor.cpp | 82 |
1 files changed, 31 insertions, 51 deletions
diff --git a/media/libstagefright/MP3Extractor.cpp b/media/libstagefright/MP3Extractor.cpp index c168771..f9251e1 100644 --- a/media/libstagefright/MP3Extractor.cpp +++ b/media/libstagefright/MP3Extractor.cpp @@ -311,15 +311,19 @@ static bool Resync( // Skip an optional ID3 header if syncing at the very beginning // of the datasource. - uint8_t id3header[10]; - if (source->readAt(0, id3header, sizeof(id3header)) - < (ssize_t)sizeof(id3header)) { - // If we can't even read these 10 bytes, we might as well bail out, - // even if there _were_ 10 bytes of valid mp3 audio data... - return false; - } + for (;;) { + uint8_t id3header[10]; + if (source->readAt(*inout_pos, id3header, sizeof(id3header)) + < (ssize_t)sizeof(id3header)) { + // If we can't even read these 10 bytes, we might as well bail + // out, even if there _were_ 10 bytes of valid mp3 audio data... + return false; + } + + if (memcmp("ID3", id3header, 3)) { + break; + } - if (id3header[0] == 'I' && id3header[1] == 'D' && id3header[2] == '3') { // Skip the ID3v2 header. size_t len = @@ -331,50 +335,30 @@ static bool Resync( len += 10; *inout_pos += len; + + LOGV("skipped ID3 tag, new starting offset is %ld (0x%08lx)", + *inout_pos, *inout_pos); } } - const size_t kMaxFrameSize = 4096; - uint8_t *buffer = new uint8_t[kMaxFrameSize]; - - off_t pos = *inout_pos - kMaxFrameSize; - size_t buffer_offset = kMaxFrameSize; - size_t buffer_length = kMaxFrameSize; + off_t pos = *inout_pos; bool valid = false; do { - if (buffer_offset + 3 >= buffer_length) { - if (buffer_length < kMaxFrameSize) { - break; - } - - pos += buffer_offset; - - if (pos >= *inout_pos + 128 * 1024) { - // Don't scan forever. - LOGV("giving up at offset %ld", pos); - break; - } - - memmove(buffer, &buffer[buffer_offset], buffer_length - buffer_offset); - buffer_length = buffer_length - buffer_offset; - buffer_offset = 0; - - ssize_t n = source->readAt( - pos, &buffer[buffer_length], kMaxFrameSize - buffer_length); - - if (n <= 0) { - break; - } - - buffer_length += (size_t)n; + if (pos >= *inout_pos + 128 * 1024) { + // Don't scan forever. + LOGV("giving up at offset %ld", pos); + break; + } - continue; + uint8_t tmp[4]; + if (source->readAt(pos, tmp, 4) != 4) { + break; } - uint32_t header = U32_AT(&buffer[buffer_offset]); + uint32_t header = U32_AT(tmp); if (match_header != 0 && (header & kMask) != (match_header & kMask)) { - ++buffer_offset; + ++pos; continue; } @@ -382,16 +366,16 @@ static bool Resync( int sample_rate, num_channels, bitrate; if (!get_mp3_frame_size(header, &frame_size, &sample_rate, &num_channels, &bitrate)) { - ++buffer_offset; + ++pos; continue; } - LOGV("found possible 1st frame at %ld", pos + buffer_offset); + LOGV("found possible 1st frame at %ld (header = 0x%08x)", pos, header); // We found what looks like a valid frame, // now find its successors. - off_t test_pos = pos + buffer_offset + frame_size; + off_t test_pos = pos + frame_size; valid = true; for (int j = 0; j < 3; ++j) { @@ -422,7 +406,7 @@ static bool Resync( } if (valid) { - *inout_pos = pos + buffer_offset; + *inout_pos = pos; if (out_header != NULL) { *out_header = header; @@ -431,13 +415,9 @@ static bool Resync( LOGV("no dice, no valid sequence of frames found."); } - ++buffer_offset; - + ++pos; } while (!valid); - delete[] buffer; - buffer = NULL; - return valid; } |