add ReadLiveLast

ffmpegcv/ffmpeg_noblock.py

@@ -2,6 +2,8 @@
 from .ffmpeg_writer_noblock import FFmpegWriterNoblock
 from typing import Callable
 import ffmpegcv
+import threading
+import numpy as np
 
 
 def noblock(fun:Callable, *v_args, **v_kargs):
@@ -16,3 +18,31 @@ def noblock(fun:Callable, *v_args, **v_kargs):
         raise ValueError('The function is not supported as a Reader or Writer')
 
     return proxyfun
+
+
+class ReadLast(threading.Thread, ffmpegcv.FFmpegReader):
+    def __init__(self, fun, *args, **kvargs):
+        threading.Thread.__init__(self)
+        ffmpegcv.FFmpegReader.__init__(self)
+        self.vid = vid = fun(*args, **kvargs)
+        self.out_numpy_shape = vid.out_numpy_shape
+        self.width, self.height = vid.width, vid.height
+        self.img = np.zeros(self.out_numpy_shape, dtype=np.uint8)
+        self.ret = True
+        self._isopen = True
+        self.start()
+
+    def read(self):
+        if self.ret:
+            self.iframe += 1
+        return self.ret, self.img
+
+    def release(self):
+        self._isopen = False
+        self.vid.release()
+
+    def run(self):
+        while self._isopen:
+            self.ret, self.img = self.vid.read()
+            if self.ret:
+                break

ffmpegcv/ffmpeg_reader_stream_realtime.py

@@ -22,7 +22,6 @@ def VideoReader(
             '-rtsp_transport tcp '
             '-fflags nobuffer -flags low_delay -strict experimental '
             f' -i {stream_url}'
-            #'-vf extractplanes=y '
             f" -pix_fmt {pix_fmt}  -f rawvideo pipe:"
         )
 
@@ -40,11 +39,6 @@ def VideoReader(
         }[pix_fmt]
         vid.process = run_async(vid.ffmpeg_cmd)
         vid.isopened = True
-        # producer
-        # vid.step = 1
-        # vid.q = Queue(maxsize=30)
-        # producer = ProducerThread(vid, vid.q)
-        # producer.start()
         return vid
 
     def read(self):
@@ -55,4 +49,4 @@ def read(self):
         self.iframe += 1
         img = None
         img = np.frombuffer(in_bytes, np.uint8).reshape(self.out_numpy_shape)
-        return True, img
+        return True, img