feat: add support of codec plugin

ext-codec/G711.cpp

@@ -0,0 +1,188 @@
+/*
+ * Copyright (c) 2016-present The ZLMediaKit project authors. All Rights Reserved.
+ *
+ * This file is part of ZLMediaKit(https://github.com/ZLMediaKit/ZLMediaKit).
+ *
+ * Use of this source code is governed by MIT-like license that can be found in the
+ * LICENSE file in the root of the source tree. All contributing project authors
+ * may be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "G711.h"
+#include "G711Rtp.h"
+#include "Extension/Factory.h"
+#include "Extension/CommonRtp.h"
+#include "Extension/CommonRtmp.h"
+
+using namespace std;
+using namespace toolkit;
+
+namespace mediakit {
+
+/**
+ * G711类型SDP
+ */
+class G711Sdp : public Sdp {
+public:
+    /**
+     * G711采样率固定为8000
+     * @param codecId G711A G711U
+     * @param payload_type rtp payload type
+     * @param sample_rate 音频采样率
+     * @param channels 通道数
+     * @param bitrate 比特率
+     */
+    G711Sdp(CodecId codecId, int payload_type, int sample_rate, int channels, int bitrate)
+        : Sdp(sample_rate, payload_type) {
+        _printer << "m=audio 0 RTP/AVP " << payload_type << "\r\n";
+        if (bitrate) {
+            _printer << "b=AS:" << bitrate << "\r\n";
+        }
+        _printer << "a=rtpmap:" << payload_type << " " << getCodecName(codecId) << "/" << sample_rate  << "/" << channels << "\r\n";
+    }
+
+    string getSdp() const override {
+        return _printer;
+    }
+
+private:
+    _StrPrinter _printer;
+};
+
+Track::Ptr G711Track::clone() const {
+    return std::make_shared<G711Track>(*this);
+}
+
+Sdp::Ptr G711Track::getSdp(uint8_t payload_type) const {
+    if (!ready()) {
+        WarnL << getCodecName() << " Track未准备好";
+        return nullptr;
+    }
+
+    const auto codec = getCodecId();
+    const auto sample_rate = getAudioSampleRate();
+    const auto audio_channel = getAudioChannel();
+    const auto bitrate = getBitRate() >> 10;
+    if (sample_rate == 8000 && audio_channel == 1) {
+        // https://datatracker.ietf.org/doc/html/rfc3551#section-6
+        payload_type = (codec == CodecG711U) ? Rtsp::PT_PCMU : Rtsp::PT_PCMA;
+    }
+
+    return std::make_shared<G711Sdp>(codec, payload_type, sample_rate, audio_channel, bitrate);
+}
+
+
+namespace {
+
+CodecId getCodecA() {
+    return CodecG711A;
+}
+
+CodecId getCodecU() {
+    return CodecG711A;
+}
+
+Track::Ptr getTrackByCodecId_l(CodecId codec, int sample_rate, int channels, int sample_bit) {
+    return (sample_rate && channels && sample_bit) ? std::make_shared<G711Track>(codec, sample_rate, channels, sample_bit) : nullptr;
+}
+
+Track::Ptr getTrackByCodecIdA(int sample_rate, int channels, int sample_bit) {
+    return getTrackByCodecId_l(CodecG711A, sample_rate, channels, sample_bit);
+}
+
+Track::Ptr getTrackByCodecIdU(int sample_rate, int channels, int sample_bit) {
+    return getTrackByCodecId_l(CodecG711U, sample_rate, channels, sample_bit);
+}
+
+Track::Ptr getTrackBySdp_l(CodecId codec, const SdpTrack::Ptr &track) {
+    return std::make_shared<G711Track>(codec, track->_samplerate, track->_channel, 16);
+}
+
+Track::Ptr getTrackBySdpA(const SdpTrack::Ptr &track) {
+    return getTrackBySdp_l(CodecG711A, track);
+}
+
+Track::Ptr getTrackBySdpU(const SdpTrack::Ptr &track) {
+    return getTrackBySdp_l(CodecG711U, track);
+}
+
+RtpCodec::Ptr getRtpEncoderByCodecId_l(CodecId codec, uint8_t pt) {
+    if (pt == Rtsp::PT_PCMA || pt == Rtsp::PT_PCMU) {
+        return std::make_shared<G711RtpEncoder>(codec, 1);
+    }
+    return std::make_shared<CommonRtpEncoder>();
+}
+
+RtpCodec::Ptr getRtpEncoderByCodecIdA(uint8_t pt) {
+    return getRtpEncoderByCodecId_l(CodecG711A, pt);
+}
+
+RtpCodec::Ptr getRtpEncoderByCodecIdU(uint8_t pt) {
+    return getRtpEncoderByCodecId_l(CodecG711U, pt);
+}
+
+RtpCodec::Ptr getRtpDecoderByCodecId_l(CodecId codec) {
+    return std::make_shared<CommonRtpDecoder>(codec);
+}
+
+RtpCodec::Ptr getRtpDecoderByCodecIdA() {
+    return getRtpDecoderByCodecId_l(CodecG711A);
+}
+
+RtpCodec::Ptr getRtpDecoderByCodecIdU() {
+    return getRtpDecoderByCodecId_l(CodecG711U);
+}
+
+RtmpCodec::Ptr getRtmpEncoderByTrack(const Track::Ptr &track) {
+    auto audio_track = dynamic_pointer_cast<AudioTrack>(track);
+    if (audio_track->getAudioSampleRate() != 8000 || audio_track->getAudioChannel() != 1 || audio_track->getAudioSampleBit() != 16) {
+        //rtmp对g711只支持8000/1/16规格，但是ZLMediaKit可以解析其他规格的G711
+        WarnL << "RTMP only support G711 with 8000/1/16, now is"
+              << audio_track->getAudioSampleRate() << "/"
+              << audio_track->getAudioChannel() << "/"
+              << audio_track->getAudioSampleBit()
+              << ", ignored it";
+        return nullptr;
+    }
+    return std::make_shared<CommonRtmpEncoder>(track);
+}
+
+RtmpCodec::Ptr getRtmpDecoderByTrack(const Track::Ptr &track) {
+    return std::make_shared<CommonRtmpDecoder>(track);
+}
+
+Frame::Ptr getFrameFromPtr_l(CodecId codec, const char *data, size_t bytes, uint64_t dts, uint64_t pts) {
+    return std::make_shared<FrameFromPtr>(codec, (char *)data, bytes, dts, pts);
+}
+
+Frame::Ptr getFrameFromPtrA(const char *data, size_t bytes, uint64_t dts, uint64_t pts) {
+    return getFrameFromPtr_l(CodecG711A, (char *)data, bytes, dts, pts);
+}
+
+Frame::Ptr getFrameFromPtrU(const char *data, size_t bytes, uint64_t dts, uint64_t pts) {
+    return getFrameFromPtr_l(CodecG711U, (char *)data, bytes, dts, pts);
+}
+
+} // namespace
+
+CodecPlugin g711a_plugin = { getCodecA,
+                             getTrackByCodecIdA,
+                             getTrackBySdpA,
+                             getRtpEncoderByCodecIdA,
+                             getRtpDecoderByCodecIdA,
+                             getRtmpEncoderByTrack,
+                             getRtmpDecoderByTrack,
+                             getFrameFromPtrA };
+
+CodecPlugin g711u_plugin = { getCodecU,
+                             getTrackByCodecIdU,
+                             getTrackBySdpU,
+                             getRtpEncoderByCodecIdU,
+                             getRtpDecoderByCodecIdU,
+                             getRtmpEncoderByTrack,
+                             getRtmpDecoderByTrack,
+                             getFrameFromPtrA };
+
+}//namespace mediakit
+
+