Start supporting H264 packetization mode 0.

The work was already done to support it, but it wasn't being negotiated
in SDP.

This means we'll now see 8 H264 payload types instead of 4; one for each
combination of BP/CBP profiles, packetization modes 0/1, and RTX/non-RTX.
This could be problematic in the future, since we're starting to run
out of dynamic payload types (using 25 of 32).

Bug: chromium:600254
Change-Id: Ief2340db77c796f12980445b547b87e939170fae
Reviewed-on: https://webrtc-review.googlesource.com/77264
Commit-Queue: Taylor Brandstetter <deadbeef@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Magnus Jedvert <magjed@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23372}
This commit is contained in:
Taylor Brandstetter
2018-05-16 15:27:41 -07:00
committed by Commit Bot
parent 70bb326fa4
commit 3409cfa378

View File

@ -40,14 +40,17 @@ bool IsH264CodecSupported() {
#endif
}
SdpVideoFormat CreateH264Format(H264::Profile profile, H264::Level level) {
SdpVideoFormat CreateH264Format(H264::Profile profile,
H264::Level level,
const std::string& packetization_mode) {
const rtc::Optional<std::string> profile_string =
H264::ProfileLevelIdToString(H264::ProfileLevelId(profile, level));
RTC_CHECK(profile_string);
return SdpVideoFormat(cricket::kH264CodecName,
{{cricket::kH264FmtpProfileLevelId, *profile_string},
{cricket::kH264FmtpLevelAsymmetryAllowed, "1"},
{cricket::kH264FmtpPacketizationMode, "1"}});
return SdpVideoFormat(
cricket::kH264CodecName,
{{cricket::kH264FmtpProfileLevelId, *profile_string},
{cricket::kH264FmtpLevelAsymmetryAllowed, "1"},
{cricket::kH264FmtpPacketizationMode, packetization_mode}});
}
} // namespace
@ -67,8 +70,15 @@ std::vector<SdpVideoFormat> SupportedH264Codecs() {
// decoder for that profile is required to be able to decode CBP. This means
// we can encode and send CBP even though we negotiated a potentially
// higher profile. See the H264 spec for more information.
return {CreateH264Format(H264::kProfileBaseline, H264::kLevel3_1),
CreateH264Format(H264::kProfileConstrainedBaseline, H264::kLevel3_1)};
//
// We support both packetization modes 0 (mandatory) and 1 (optional,
// preferred).
return {
CreateH264Format(H264::kProfileBaseline, H264::kLevel3_1, "1"),
CreateH264Format(H264::kProfileBaseline, H264::kLevel3_1, "0"),
CreateH264Format(H264::kProfileConstrainedBaseline, H264::kLevel3_1, "1"),
CreateH264Format(H264::kProfileConstrainedBaseline, H264::kLevel3_1,
"0")};
}
std::unique_ptr<H264Encoder> H264Encoder::Create(