script to compact frames to y4m video

Change-Id: I2d8c3ccf49c172a54181aeb2e2b8169bf5402456

diff --git a/tools/3D-Reconstruction/genY4M/genY4M.py b/tools/3D-Reconstruction/genY4M/genY4M.py
new file mode 100644 (file)
index 0000000..4b640e3
--- /dev/null
+++ b/tools/3D-Reconstruction/genY4M/genY4M.py
@@ -0,0 +1,76 @@
+import argparse
+from os import listdir, path
+from PIL import Image
+import sys
+
+parser = argparse.ArgumentParser()
+parser.add_argument("--frame_path", default="../data/frame/", type=str)
+parser.add_argument("--frame_rate", default="25:1", type=str)
+parser.add_argument("--interlacing", default="Ip", type=str)
+parser.add_argument("--pix_ratio", default="0:0", type=str)
+parser.add_argument("--color_space", default="4:2:0", type=str)
+parser.add_argument("--output", default="output.y4m", type=str)
+
+
+def generate(args, frames):
+  if len(frames) == 0:
+    return
+  #sort the frames based on the frame index
+  frames = sorted(frames, key=lambda x: x[0])
+  #convert the frames to YUV form
+  frames = [f.convert("YCbCr") for _, f in frames]
+  #write the header
+  header = "YUV4MPEG2 W%d H%d F%s %s A%s" % (frames[0].width, frames[0].height,
+                                             args.frame_rate, args.interlacing,
+                                             args.pix_ratio)
+  cs = args.color_space.split(":")
+  header += " C%s%s%s\n" % (cs[0], cs[1], cs[2])
+  #estimate the sample step based on subsample value
+  subsamples = [int(c) for c in cs]
+  r_step = [1, int(subsamples[2] == 0) + 1, int(subsamples[2] == 0) + 1]
+  c_step = [1, 4 // subsamples[1], 4 // subsamples[1]]
+  #write in frames
+  with open(args.output, "wb") as y4m:
+    y4m.write(header)
+    for f in frames:
+      y4m.write("FRAME\n")
+      px = f.load()
+      for k in xrange(3):
+        for i in xrange(0, f.height, r_step[k]):
+          for j in xrange(0, f.width, c_step[k]):
+            yuv = px[j, i]
+            y4m.write(chr(yuv[k]))
+
+
+if __name__ == "__main__":
+  args = parser.parse_args()
+  frames = []
+  frames_mv = []
+  for filename in listdir(args.frame_path):
+    name, ext = filename.split(".")
+    if ext == "png":
+      name_parse = name.split("_")
+      idx = int(name_parse[-1])
+      img = Image.open(path.join(args.frame_path, filename))
+      if name_parse[-2] == "mv":
+        frames_mv.append((idx, img))
+      else:
+        frames.append((idx, img))
+  if len(frames) == 0:
+    print "No frames in directory: " + args.frame_path
+    sys.exit()
+  print("----------------------Y4M Info----------------------")
+  print("width:  %d" % frames[0][1].width)
+  print("height: %d" % frames[0][1].height)
+  print("#frame: %d" % len(frames))
+  print("frame rate: %s" % args.frame_rate)
+  print("interlacing: %s" % args.interlacing)
+  print("pixel ratio: %s" % args.pix_ratio)
+  print("color space: %s" % args.color_space)
+  print("----------------------------------------------------")
+
+  print("Generating ...")
+  generate(args, frames)
+  if len(frames_mv) != 0:
+    args.output = args.output.replace(".y4m", "_mv.y4m")
+    generate(args, frames_mv)