新增对mp2音视频编码格式的支持

2026-06-18 06:02:21 +08:00 · 2026-03-09 21:19:05 +08:00
parent 5d4a266873
commit bb903fddcd
12 changed files with 1176 additions and 3 deletions
--- a/ext-codec/MP2ARtp.h
+++ b/ext-codec/MP2ARtp.h
@@ -0,0 +1,87 @@
+/*
+ * 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_MP2ARTP_H
+#define ZLMEDIAKIT_MP2ARTP_H
+
+#include "MP2A.h"
+#include "Rtsp/RtpCodec.h"
+
+namespace mediakit {
+
+// RFC 2250 Section 3.5 MPEG Audio-specific header (4 bytes)
+//
+//  0               1               2               3
+//  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+// |             MBZ               |          Frag_offset          |
+// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+//
+// MBZ: Must Be Zero (16 bits)
+// Frag_offset: Byte offset into the audio frame for the data in this packet (16 bits)
+
+static constexpr size_t kMP2AHeaderSize = 4;
+
+/**
+ * MP2A (MPEG-1/2 Audio Layer I/II) RTP 编码器
+ * RFC 2250 Section 3.5
+ */
+class MP2ARtpEncoder : public RtpCodec {
+public:
+    using Ptr = std::shared_ptr<MP2ARtpEncoder>;
+
+    /**
+     * 输入 MPEG Audio 帧并打包为 RTP
+     * @param frame 帧数据
+     */
+    bool inputFrame(const Frame::Ptr &frame) override;
+
+private:
+    /**
+     * 输出一个 RTP 包
+     * @param data ES 数据
+     * @param len 数据长度
+     * @param frag_offset 分片在帧内的偏移
+     * @param mark 是否为帧最后一个包
+     * @param stamp 时间戳(ms)
+     */
+    void outputRtp(const char *data, size_t len, size_t frag_offset, bool mark, uint64_t stamp);
+};
+
+/**
+ * MP2A (MPEG-1/2 Audio Layer I/II) RTP 解码器
+ * RFC 2250 Section 3.5
+ */
+class MP2ARtpDecoder : public RtpCodec {
+public:
+    using Ptr = std::shared_ptr<MP2ARtpDecoder>;
+
+    MP2ARtpDecoder();
+
+    /**
+     * 输入 MPEG Audio RTP 包并解码
+     * @param rtp rtp 数据包
+     * @param key_pos 音频帧忽略此参数
+     */
+    bool inputRtp(const RtpPacket::Ptr &rtp, bool key_pos = false) override;
+
+private:
+    void obtainFrame();
+    void flushData();
+
+private:
+    uint16_t _last_seq = 0;
+    uint32_t _last_stamp = 0;
+    FrameImp::Ptr _frame;
+};
+
+} // namespace mediakit
+
+#endif // ZLMEDIAKIT_MP2ARTP_H