feat: add support of codec plugin

ext-codec/H264.h

@@ -0,0 +1,135 @@
+/*
+ * 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.
+ */
+
+#ifndef ZLMEDIAKIT_H264_H
+#define ZLMEDIAKIT_H264_H
+
+#include "Extension/Frame.h"
+#include "Extension/Track.h"
+
+#define H264_TYPE(v) ((uint8_t)(v) & 0x1F)
+
+namespace mediakit{
+
+void splitH264(const char *ptr, size_t len, size_t prefix, const std::function<void(const char *, size_t, size_t)> &cb);
+size_t prefixSize(const char *ptr, size_t len);
+
+template<typename Parent>
+class H264FrameHelper : public Parent{
+public:
+    friend class FrameImp;
+    friend class toolkit::ResourcePool_l<H264FrameHelper>;
+    using Ptr = std::shared_ptr<H264FrameHelper>;
+
+    enum {
+        NAL_IDR = 5,
+        NAL_SEI = 6,
+        NAL_SPS = 7,
+        NAL_PPS = 8,
+        NAL_AUD = 9,
+        NAL_B_P = 1,
+    };
+
+    template<typename ...ARGS>
+    H264FrameHelper(ARGS &&...args): Parent(std::forward<ARGS>(args)...) {
+        this->_codec_id = CodecH264;
+    }
+
+    bool keyFrame() const override {
+        auto nal_ptr = (uint8_t *) this->data() + this->prefixSize();
+        return H264_TYPE(*nal_ptr) == NAL_IDR && decodeAble();
+    }
+
+    bool configFrame() const override {
+        auto nal_ptr = (uint8_t *) this->data() + this->prefixSize();
+        switch (H264_TYPE(*nal_ptr)) {
+            case NAL_SPS:
+            case NAL_PPS: return true;
+            default: return false;
+        }
+    }
+
+    bool dropAble() const override {
+        auto nal_ptr = (uint8_t *) this->data() + this->prefixSize();
+        switch (H264_TYPE(*nal_ptr)) {
+            case NAL_SEI:
+            case NAL_AUD: return true;
+            default: return false;
+        }
+    }
+
+    bool decodeAble() const override {
+        auto nal_ptr = (uint8_t *) this->data() + this->prefixSize();
+        auto type = H264_TYPE(*nal_ptr);
+        //多slice情况下, first_mb_in_slice 表示其为一帧的开始
+        return type >= NAL_B_P && type <= NAL_IDR && (nal_ptr[1] & 0x80);
+    }
+};
+
+/**
+ * 264帧类
+ */
+using H264Frame = H264FrameHelper<FrameImp>;
+
+/**
+ * 防止内存拷贝的H264类
+ * 用户可以通过该类型快速把一个指针无拷贝的包装成Frame类
+ */
+using H264FrameNoCacheAble = H264FrameHelper<FrameFromPtr>;
+
+/**
+ * 264视频通道
+ */
+class H264Track : public VideoTrack {
+public:
+    using Ptr = std::shared_ptr<H264Track>;
+
+    /**
+     * 不指定sps pps构造h264类型的媒体
+     * 在随后的inputFrame中获取sps pps
+     */
+    H264Track() = default;
+
+    /**
+     * 构造h264类型的媒体
+     * @param sps sps帧数据
+     * @param pps pps帧数据
+     * @param sps_prefix_len 264头长度，可以为3个或4个字节，一般为0x00 00 00 01
+     * @param pps_prefix_len 264头长度，可以为3个或4个字节，一般为0x00 00 00 01
+     */
+    H264Track(const std::string &sps, const std::string &pps, int sps_prefix_len = 4, int pps_prefix_len = 4);
+
+    bool ready() const override;
+    CodecId getCodecId() const override;
+    int getVideoHeight() const override;
+    int getVideoWidth() const override;
+    float getVideoFps() const override;
+    bool inputFrame(const Frame::Ptr &frame) override;
+    toolkit::Buffer::Ptr getExtraData() const override;
+    void setExtraData(const uint8_t *data, size_t size) override;
+    bool update() override;
+
+private:
+    Sdp::Ptr getSdp(uint8_t payload_type) const override;
+    Track::Ptr clone() const override;
+    bool inputFrame_l(const Frame::Ptr &frame);
+    void insertConfigFrame(const Frame::Ptr &frame);
+
+private:
+    bool _latest_is_config_frame = false;
+    int _width = 0;
+    int _height = 0;
+    float _fps = 0;
+    std::string _sps;
+    std::string _pps;
+};
+
+}//namespace mediakit
+#endif //ZLMEDIAKIT_H264_H