bb2d6b92 by David LaPalomento

Add notes on sample offset calculation

Write up some basic reminders of valid ways to address samples in a fragmented MP4 when using movie-fragment-relative addressing.
1 parent aeaa8493
...@@ -46,4 +46,30 @@ track ...@@ -46,4 +46,30 @@ track
46 chunk 46 chunk
47 sample 47 sample
48 48
49 movie fragment -> track fragment -> [samples]
...\ No newline at end of file ...\ No newline at end of file
49 movie fragment -> track fragment -> [samples]
50
51 ### Sample Data Offsets
52 Movie-fragment Relative Addressing: all trun data offsets are relative
53 to the containing moof (?).
54
55 Without default-base-is-moof, the base data offset for each trun in
56 trafs after the first is the *end* of the previous traf.
57
58 #### iso5/DASH Style
59 moof
60 |- traf (default-base-is-moof)
61 | |- trun_0 <size of moof> + 0
62 | `- trun_1 <size of moof> + 100
63 `- traf (default-base-is-moof)
64 `- trun_2 <size of moof> + 300
65 mdat
66 |- samples_for_trun_0 (100 bytes)
67 |- samples_for_trun_1 (200 bytes)
68 `- samples_for_trun_2
69
70 #### Single Track Style
71 moof
72 `- traf
73 `- trun_0 <size of moof> + 0
74 mdat
75 `- samples_for_trun_0
...\ No newline at end of file ...\ No newline at end of file
......