Figure 1 shows the data reorganization that we performed prior to streaming a movie. The ‘idx1’ frame index table, which is generally located at the end of an AVI file is moved to the very beginning. The video and audio data that starts with a ‘RIFF’ four character signature is appended to the table. No other changes are made to the contents of the file.

Specifically, no internal pointers are changed to match the new frame locations. The buffer manager logic is designed to correctly and transparently translate all access locations. Its operation is described in the next few paragraphs.

For streaming, one disadvantage ofmoving the frame table to the beginning of the file is that playback can only start after the complete table has been received at the client side. However, Table 1 shows that generally the frame table size is less than 1% of the complete size of a movie and does therefore not introduce significant startup latencies.