Before this CL, when we encoded a sequence with a non-existent
base, we pretended that the delta was 0, and the first delta was
based on that. However, in a sequence where the deltas are small,
but where the first element is big, that would produce
unnecessarily wide deltas. Therefore, we change the behavior in
cases where the base is non-existent, to encode the first existent
value (if any) as a varint; the delta width may then be smaller.
This CL include two piggy-backed changes:
1. Varint encoding/decoding moved to its own file (and an
additional flavor added).
2. The unit tests for delta encoding are further parameterized
with a random seed.
Bug: webrtc:8111
Change-Id: I76fff577c86d019c8334bf74b76bd35db06ff68d
Reviewed-on: https://webrtc-review.googlesource.com/c/107860
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25395}
Optional fields are those which only occur sometimes. For example,
the sequence number field in an RTP packet always occurs, but
fields in optional RTP extensions only occur sometimes.
Bug: webrtc:8111
Change-Id: Iff2c35b73530c0a1db68e547b4caf34434aa4ace
Reviewed-on: https://webrtc-review.googlesource.com/c/103362
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25336}
Signed deltas can yield a more efficient encoding when the encoded
sequence sometimes moves backwards.
Bug: webrtc:8111
Change-Id: Ib1a50192851214ccc3f2bd7eaf88f4be97e4beb0
Reviewed-on: https://webrtc-review.googlesource.com/c/100423
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25324}
Add code for delta-encoding and decoding, to be used when producing
WebRTC event logs of the new format.
This CL supports fixed-size encoding only. Also, no support for
signed deltas or optional values yet. These will be added in
subsequent CLs.
Bug: webrtc:8111
Change-Id: I531abd99fd924f4c9e692abe565bc6f66c875ad5
Reviewed-on: https://webrtc-review.googlesource.com/c/100304
Reviewed-by: Björn Terelius <terelius@webrtc.org>
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25256}
