webrtc/modules/video_coding/codecs/h264/h264.cc
Taylor Brandstetter 28deb90728 Reland "Start supporting H264 packetization mode 0."
This is a reland of 3409cfa378

Needed to change RtpVideoStreamReceiver to stop deregistering a payload
type if two payload types refer to the same codec (which now happens,
with the packetization mode 0/1 payload types). It's not clear why this
was being done in the first place.

Original change's description:
> 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}

Bug: chromium:600254
Change-Id: Ice1acc05acd1543d9b46e918de2bba0694d86259
Reviewed-on: https://webrtc-review.googlesource.com/78399
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Taylor Brandstetter <deadbeef@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23494}
2018-06-01 18:03:06 +00:00

117 lines
3.5 KiB
C++

/*
* Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*
*/
#include "modules/video_coding/codecs/h264/include/h264.h"
#include "api/video_codecs/sdp_video_format.h"
#include "media/base/h264_profile_level_id.h"
#if defined(WEBRTC_USE_H264)
#include "modules/video_coding/codecs/h264/h264_decoder_impl.h"
#include "modules/video_coding/codecs/h264/h264_encoder_impl.h"
#endif
#include "rtc_base/checks.h"
#include "rtc_base/logging.h"
#include "rtc_base/ptr_util.h"
namespace webrtc {
namespace {
#if defined(WEBRTC_USE_H264)
bool g_rtc_use_h264 = true;
#endif
// If H.264 OpenH264/FFmpeg codec is supported.
bool IsH264CodecSupported() {
#if defined(WEBRTC_USE_H264)
return g_rtc_use_h264;
#else
return false;
#endif
}
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, packetization_mode}});
}
} // namespace
void DisableRtcUseH264() {
#if defined(WEBRTC_USE_H264)
g_rtc_use_h264 = false;
#endif
}
std::vector<SdpVideoFormat> SupportedH264Codecs() {
if (!IsH264CodecSupported())
return std::vector<SdpVideoFormat>();
// We only support encoding Constrained Baseline Profile (CBP), but the
// decoder supports more profiles. We can list all profiles here that are
// supported by the decoder and that are also supersets of CBP, i.e. the
// 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.
//
// 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(
const cricket::VideoCodec& codec) {
RTC_DCHECK(H264Encoder::IsSupported());
#if defined(WEBRTC_USE_H264)
RTC_CHECK(g_rtc_use_h264);
RTC_LOG(LS_INFO) << "Creating H264EncoderImpl.";
return rtc::MakeUnique<H264EncoderImpl>(codec);
#else
RTC_NOTREACHED();
return nullptr;
#endif
}
bool H264Encoder::IsSupported() {
return IsH264CodecSupported();
}
std::unique_ptr<H264Decoder> H264Decoder::Create() {
RTC_DCHECK(H264Decoder::IsSupported());
#if defined(WEBRTC_USE_H264)
RTC_CHECK(g_rtc_use_h264);
RTC_LOG(LS_INFO) << "Creating H264DecoderImpl.";
return rtc::MakeUnique<H264DecoderImpl>();
#else
RTC_NOTREACHED();
return nullptr;
#endif
}
bool H264Decoder::IsSupported() {
return IsH264CodecSupported();
}
} // namespace webrtc