getVideoHeight(), getVideoWidth() and getVideoFps() in JPEGTrack

src/Extension/JPEG.cpp

@@ -6,6 +6,29 @@ using namespace toolkit;
 
 namespace mediakit {
 
+bool JPEGTrack::inputFrame(const Frame::Ptr &frame) {
+    if (!ready()) {
+        if ((_height & _width) > 0) {
+            if (_tmp == 0) _tmp = frame->dts();
+            else _fps = 1000.0 / (frame->dts() - _tmp);
+        } else getVideoResolution((uint8_t*)frame->data(), frame->size());
+        return false;
+    }
+    return VideoTrack::inputFrame(frame);
+}
+
+void JPEGTrack::getVideoResolution(const uint8_t *buf, int len) {
+    for (int i = 0; i < len - 8; i++) {
+        if (buf[i] != 0xff)
+            continue;
+        if (buf[i + 1] == 0xC0 /*SOF0*/) {
+            _height = buf[i + 5] * 256 + buf[i + 6];
+            _width = buf[i + 7] * 256 + buf[i + 8];
+            return;
+        }
+    }
+}
+
 class JPEGSdp : public Sdp {
 public:
     JPEGSdp(int bitrate): Sdp(90000, Rtsp::PT_JPEG) {

src/Extension/JPEG.h

@@ -14,17 +14,19 @@ public:
     int getVideoHeight() const override { return _height; }
     int getVideoWidth() const override { return _width; }
     float getVideoFps() const override { return _fps; }
-    bool ready() override { return true; }
-    bool inputFrame(const Frame::Ptr &frame) override { return VideoTrack::inputFrame(frame); }
+    bool ready() override { return _fps > 0; }
+    bool inputFrame(const Frame::Ptr &frame) override;
 
 private:
     Sdp::Ptr getSdp() override;
     Track::Ptr clone() override { return std::make_shared<std::remove_reference<decltype(*this)>::type>(*this); }
+    void getVideoResolution(const uint8_t *buf, int len);
 
 private:
     int _width = 0;
     int _height = 0;
     float _fps = 0;
+    uint64_t _tmp = 0;
 };
 
 class JPEGFrame : public Frame {