Encoder: 4bit color, space out RS chunks

1 files changed, 21 insertions, 18 deletions

diff --git a/encoder.py b/encoder.py
index 5752d55..4b71bf4 100644
--- a/encoder.py
+++ b/encoder.py
@@ -23,22 +23,24 @@ args = parser.parse_args()
 cheight = cwidth = max(args.height // 10, args.width // 10)
 midwidth = args.width - 2 * cwidth
 frame_size = args.height * args.width - 4 * cheight * cwidth
-frame_xor = np.arange(frame_size, dtype=np.uint8)
+frame_xor = np.arange(frame_size // 2, dtype=np.uint8)
 # reedsolo breaks message into 255-byte chunks
 # raptorq can add up to 4 extra bytes
-rs_size = frame_size - int((frame_size + 254) / 255) * int(args.level * 255) - 4
+# Divide by 2 for 4-bit color
+rs_size = frame_size - (frame_size // 2 + 254) // 255 * int(args.level * 255) - 4
 
 with open(args.input, "rb") as f:
     data = f.read()
 rsc = RSCodec(int(args.level * 255))
 encoder = Encoder.with_defaults(data, rs_size)
+# This formula is wrong 🤷
 packets = encoder.get_encoded_packets(int(len(data) / rs_size * args.level))
 
 # Make corners
-wcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b11111111), ((0, 1), (0, 1)))
-rcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b00000111), ((0, 1), (1, 0)))
-gcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b00111000), ((1, 0), (0, 1)))
-bcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b11000000), ((1, 0), (1, 0)))
+wcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b1111), ((0, 1), (0, 1)))
+rcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b0001), ((0, 1), (1, 0)))
+gcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b0110), ((1, 0), (0, 1)))
+bcorner = np.pad(np.full((cheight - 1, cwidth - 1), 0b1000), ((1, 0), (1, 0)))
 
 print("Data length:", len(data))
 print("Packets:", len(packets))
@@ -48,29 +50,30 @@ idx = 0
 
 def get_frame():
     global idx
-    frame_data = np.array(rsc.encode(packets[idx]))
-    # Pad frame to fit frame_size since raptorq might not add 4 bytes
-    frame_data = np.pad(frame_data, (0, frame_size - len(frame_data))) ^ frame_xor
-    if idx == 0:
-        print(list(frame_data))
+    frame = np.array(rsc.encode(packets[idx]))
     idx = (idx + 1) % len(packets)
+    # Add 4 bytes, pad frame to be multiple of 255
+    frame = np.pad(frame, (0, (len(frame) + 258) // 255 * 255 - len(frame)))
+    # Space out elements in each size 255 chunk
+    frame = np.ravel(np.reshape(frame, (len(frame) // 255, 255)), "F")[: frame_size // 2] ^ frame_xor
+    frame = np.ravel(np.column_stack((frame >> 4, frame & 0b1111)))
     frame = np.concatenate(
         (
             np.concatenate(
-                (wcorner, frame_data[: cheight * midwidth].reshape((cheight, midwidth)), rcorner),
+                (wcorner, frame[: cheight * midwidth].reshape((cheight, midwidth)), rcorner),
                 axis=1,
             ),
-            frame_data[cheight * midwidth : frame_size - cheight * midwidth].reshape(
+            frame[cheight * midwidth : frame_size - cheight * midwidth].reshape(
                 (args.height - 2 * cheight, args.width)
             ),
             np.concatenate(
-                (gcorner, frame_data[frame_size - cheight * midwidth :].reshape((cheight, midwidth)), bcorner),
+                (gcorner, frame[frame_size - cheight * midwidth :].reshape((cheight, midwidth)), bcorner),
                 axis=1,
             ),
         )
     )
     return np.stack(
-        ((frame & 0b00000111) * 255 // 7, (frame >> 3 & 0b00000111) * 255 // 7, (frame >> 6) * 255 // 3),
+        ((frame & 0b0001) * 255, (frame >> 1 & 0b0011) * 255 / 3, (frame >> 3) * 255),
         axis=-1,
     ).astype(np.uint8)
 
@@ -102,7 +105,7 @@ if args.output:
         width = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH))
         hscale = height // args.height
         wscale = width // args.width
-        out = cv2.VideoWriter(args.output, cv2.VideoWriter_fourcc(*"mp4v"), args.fps, (width, height))
+        out = cv2.VideoWriter(args.output, cv2.VideoWriter_fourcc(*"RGBA"), args.fps, (width, height))
         while cap.isOpened():
             ret, frame = cap.read()
             if not ret:
@@ -119,9 +122,9 @@ if args.output:
                 )
             )
     else:
-        out = cv2.VideoWriter(args.output, cv2.VideoWriter_fourcc(*"mp4v"), args.fps, (4* args.width, 4*args.height))
+        out = cv2.VideoWriter(args.output, cv2.VideoWriter_fourcc(*"RGBA"), args.fps, (args.width, args.height))
         for _ in packets:
-            out.write(cv2.cvtColor(np.repeat(np.repeat(get_frame(), 4, 0), 4, 1), cv2.COLOR_RGB2BGR))
+            out.write(cv2.cvtColor(get_frame(), cv2.COLOR_RGB2BGR))
 else:
     input("Seizure warning!")
     app = QApplication([])