a

a.py

@@ -0,0 +1,267 @@
+import struct
+class ICMP6:
+    _ICMP_ECHO_REQUEST       = 128
+    def __init__(self, destination, id, sequence, payload=None,
+            payload_size=56, ttl=64, traffic_class=0):
+
+        if payload is not None:
+            payload_size = len(payload)
+        else:
+            payload = b'\x00'*payload_size
+
+        self._destination = destination
+        self._id = id & 0xffff
+        self._sequence = sequence & 0xffff
+        self._payload = payload
+        self._payload_size = payload_size
+        self._ttl = ttl
+        self._traffic_class = traffic_class
+        self._time = 0
+    def _checksum(self, data):
+        '''
+        Compute the checksum of an ICMP packet. Checksums are used to
+        verify the integrity of packets.
+        '''
+        sum = 0
+        data += b'\x00'
+
+        for i in range(0, len(data) - 1, 2):
+            sum += (data[i] << 8) + data[i + 1]
+            sum  = (sum & 0xffff) + (sum >> 16)
+
+        sum = ~sum & 0xffff
+
+        return sum
+    def _create_packet(self):
+        '''
+        Build an ICMP packet from an identifier, a sequence number and
+        a payload.
+        This method returns the newly created ICMP header concatenated
+        to the payload passed in parameters.
+        '''
+        id, sequence, payload = self._id, self._sequence, self._payload
+        checksum = 0
+
+        # Temporary ICMP header to compute the checksum
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        checksum = self._checksum(header + payload)
+
+        # Definitive ICMP header
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        return header + payload
+
+
+
+import sys
+skip = int(sys.argv[1]) if sys.argv[1:] else 0
+slp = float(sys.argv[2]) if sys.argv[2:] else 0.0001
+slp1 = float(sys.argv[3]) if sys.argv[3:] else 0.5
+#draw_img = int(sys.argv[4]) if sys.argv[4:] else 0
+
+X=512
+Y=512
+import socket, traceback, time
+
+from PIL import Image
+#img = Image.open('1.png')
+#img = img.resize((X, Y), Image.Resampling.LANCZOS)
+#img.save('out.png')
+#img = img.convert('RGBA')
+
+imgdvd = Image.open('dvd.png')
+imgdvd = imgdvd.convert('RGBA')
+
+icmp6pkt = ICMP6(None, 0xad, 0, b'')._create_packet()
+import concurrent.futures
+def send_icmp_mt(addrs, workers=10):
+    def sendto(addr):
+        with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+            s.sendto(icmp6pkt, (addr, 0))
+        time.sleep(slp)
+    with concurrent.futures.ThreadPoolExecutor(max_workers=workers) as executor:
+        for addr in addrs:
+            executor.submit(sendto, addr)
+        executor.shutdown(wait=True, cancel_futures=False)
+def send_icmp_st(addrs):
+    try:
+        for addr in addrs:
+            with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+                s.sendto(icmp6pkt, (addr, 0))
+            time.sleep(slp)
+    except Exception:
+       traceback.print_exc()
+send_icmp = send_icmp_st
+
+headers = {'User-Agent': 'curl/7.88.1)'}
+mkreq = lambda u: urllib.request.Request(u, data=None, headers=headers)
+timeout = 60
+
+import urllib.request
+import contextlib
+import base64
+import io
+import threading
+img = None
+imglock = threading.Lock()
+def get_bg():
+    global img
+    while True:
+        try:
+            with contextlib.closing(urllib.request.urlopen(mkreq('http://us2.g-load.eu:9090/stream'), timeout=timeout)) as resp:
+                for line in resp:
+                    if line.startswith(b'data:'):
+                        with imglock:
+                            imgn = Image.open(io.BytesIO(base64.b64decode(line[5:-1])))
+                            assert imgn.size == (X, Y)
+                            #print(imgn.mode)
+                            if img is None:
+                                img = imgn.convert(mode='RGBA')
+                            else:
+                                assert imgn.mode == 'RGBA'
+                                img.paste(imgn, (0, 0), imgn)
+        except Exception:
+            traceback.print_exc()
+        print('get_bg exit')
+        time.sleep(3)
+
+def start_bg_task():
+    threading.Thread(target=get_bg, daemon=True).start()
+    while img is None:
+        time.sleep(1)
+    print('connection established')
+
+import random
+
+Dx, Dy = imgdvd.size
+sx = random.randint(0, X-1-Dx)
+sy = random.randint(0, Y-1-Dy)
+fx = random.choice((1, -1))
+fy = random.choice((1, -1))
+
+#import numpy as np
+#draw_seq = np.arange(X*Y)
+#np.random.shuffle(draw_seq)
+
+#def _spr(rangex):
+#    maxidx = len(rangex) - 1
+#    ret = []
+#    mid = maxidx // 2
+#    dl = mid
+#    dr = mid
+#    ret.append(mid)
+#    while True:
+#        if dr < maxidx:
+#            dr += 1
+#            ret.append(dr)
+#        if dl > 0:
+#            dl -= 1
+#            ret.append(dl)
+#        if dl <= 0 and dr >= maxidx:
+#            assert len(ret) - 1 == maxidx
+#            return ret
+#draw_seq = [(i // X, i % X) for i in range(X*Y)]
+#draw_seq = [(x, y) for x in _spr(range(X)) for y in _spr(range(Y))]
+draw_seq = [(x, y) for x in range(X) for y in range(Y)]
+#random.shuffle(draw_seq)
+start_bg_task()
+ldraw = Image.new(mode="RGBA", size=(X, Y))
+def draw(img):
+    global ldraw
+    send_icmp_q = []
+    start = time.time()
+    print('draw 1 frame in ', end='')
+    #for x in range(X):
+    for x, y in draw_seq:
+        #for y in range(Y):
+            #if x < skip:
+            #    continue
+        newpix = img.getpixel((x, y))
+        r, g, b, a = newpix
+        if a and newpix != ldraw.getpixel((x, y)):
+            send_icmp_q.append(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+            #print(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+            #time.sleep(slp)
+    startsend = time.time()
+    send_icmp(send_icmp_q)
+    ldraw = img.copy()
+    end = time.time()
+    print(f"{1000*(end-start):.1f}ms {1000*(end-startsend):.1f}ms")
+
+D_RGB = [0, 0, 0]
+imgdvdc = None
+def update_drgb():
+    global imgdvdc
+    D_RGB.clear()
+    D_RGB.extend([random.randint(50, 250), random.randint(50, 250), random.randint(50, 250)])
+    imgdvdc = imgdvd.copy()
+    for x in range(Dx):
+        for y in range(Dy):
+            _, _, _, a = imgdvd.getpixel((x, y))
+            imgdvdc.putpixel((x, y), (*D_RGB, a))
+update_drgb()
+import collections
+oldn = collections.deque()
+for _ in range(5):
+    oldn.append(((0, 0), Image.new(mode="RGBA", size=(Dx, Dy))))
+assert len(oldn) >= 3
+def blend(doexit=False):
+    global img
+    with imglock:
+        for old1 in oldn:
+            img.paste(old1[1], old1[0], old1[1])
+        new = img.crop((sx, sy, sx+Dx, sy+Dy))
+    oldn.append(((sx, sy), new.copy()))
+    oldn.popleft()
+    new.paste(imgdvdc, (0, 0), imgdvdc)
+    new1 = Image.new(mode="RGBA", size=(X, Y))
+    #new1 = img.copy()
+    old2 = oldn[-2]
+    new1.paste(old2[1], old2[0], old2[1])
+    if doexit:
+        old3 = oldn[-3]
+        new1.paste(old3[1], old3[0], old3[1])
+        return new1
+    new1.paste(new, (sx, sy), new)
+    #new1.save('/tmp/2.png')
+    #time.sleep(0.5)
+    return new1
+
+STEP=5
+#if draw_img:
+#    draw(img)
+try:
+    while True:
+        draw(blend())
+
+        if fx > 0:
+            if sx + Dx >= X:
+                fx = -fx
+                update_drgb()
+        else:
+            if sx <= 0:
+                fx = -fx
+                update_drgb()
+        if fy > 0:
+            if sy + Dy >= Y:
+                fy = -fy
+                update_drgb()
+        else:
+            if sy <= 0:
+                fy = -fy
+                update_drgb()
+        sx += STEP * fx
+        sy += STEP * fy
+        sx = sx if sx >= 0 else 0
+        sx = sx if sx + Dx < X else X - Dx
+        sy = sy if sy >= 0 else 0
+        sy = sy if sy + Dy < Y else Y - Dy
+        time.sleep(slp1)
+except KeyboardInterrupt:
+    print('exit...')
+    ldraw = Image.new(mode="RGBA", size=(X, Y))
+    draw(blend(doexit=True))
+    time.sleep(1)

draw-gen3.py

@@ -0,0 +1,158 @@
+#gen3
+
+import argparse
+parser = argparse.ArgumentParser()
+parser.add_argument('--skip', type=int, default=0, help="skip x lines (unused)")
+parser.add_argument('--drawfirst', action='store_true', help="draw image first (unused)")
+parser.add_argument('--slp', type=float, default=0.0001, help="sleep x seconds after each ping")
+parser.add_argument('--slp1', type=float, default=0.5, help="sleep x seconds after each frame")
+args = parser.parse_args()
+skip, slp, slp1, draw_img = args.skip, args.slp, args.slp1, args.drawfirst
+
+import struct
+class ICMP6:
+    _ICMP_ECHO_REQUEST       = 128
+    def __init__(self, destination, id, sequence, payload=None,
+            payload_size=56, ttl=64, traffic_class=0):
+
+        if payload is not None:
+            payload_size = len(payload)
+        else:
+            payload = b'\x00'*payload_size
+
+        self._destination = destination
+        self._id = id & 0xffff
+        self._sequence = sequence & 0xffff
+        self._payload = payload
+        self._payload_size = payload_size
+        self._ttl = ttl
+        self._traffic_class = traffic_class
+        self._time = 0
+    def _checksum(self, data):
+        '''
+        Compute the checksum of an ICMP packet. Checksums are used to
+        verify the integrity of packets.
+        '''
+        sum = 0
+        data += b'\x00'
+
+        for i in range(0, len(data) - 1, 2):
+            sum += (data[i] << 8) + data[i + 1]
+            sum  = (sum & 0xffff) + (sum >> 16)
+
+        sum = ~sum & 0xffff
+
+        return sum
+    def _create_packet(self):
+        '''
+        Build an ICMP packet from an identifier, a sequence number and
+        a payload.
+        This method returns the newly created ICMP header concatenated
+        to the payload passed in parameters.
+        '''
+        id, sequence, payload = self._id, self._sequence, self._payload
+        checksum = 0
+
+        # Temporary ICMP header to compute the checksum
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        checksum = self._checksum(header + payload)
+
+        # Definitive ICMP header
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        return header + payload
+
+
+X=512
+Y=512
+import socket, traceback, time
+
+from PIL import Image
+
+icmp6pkt = ICMP6(None, 0xad, 0, b'')._create_packet()
+import concurrent.futures
+def send_icmp_mt(addrs, workers=10):
+    def sendto(addr):
+        with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+            s.sendto(icmp6pkt, (addr, 0))
+        time.sleep(slp)
+    with concurrent.futures.ThreadPoolExecutor(max_workers=workers) as executor:
+        for addr in addrs:
+            executor.submit(sendto, addr)
+        executor.shutdown(wait=True, cancel_futures=False)
+def send_icmp_st(addrs):
+    try:
+        for addr in addrs:
+            with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+                s.sendto(icmp6pkt, (addr, 0))
+            time.sleep(slp)
+    except Exception:
+       traceback.print_exc()
+send_icmp = send_icmp_st
+
+headers = {'User-Agent': 'curl/7.88.1)'}
+mkreq = lambda u: urllib.request.Request(u, data=None, headers=headers)
+timeout = 60
+
+import urllib.request
+import contextlib
+import base64
+import io
+import threading
+img = None
+imglock = threading.Lock()
+def get_bg():
+    global img
+    while True:
+        try:
+            with contextlib.closing(urllib.request.urlopen(mkreq('http://us2.g-load.eu:9090/stream'), timeout=timeout)) as resp:
+                for line in resp:
+                    if line.startswith(b'data:'):
+                        with imglock:
+                            imgn = Image.open(io.BytesIO(base64.b64decode(line[5:-1])))
+                            assert imgn.size == (X, Y)
+                            #print(imgn.mode)
+                            if img is None:
+                                img = imgn.convert(mode='RGBA')
+                            else:
+                                assert imgn.mode == 'RGBA'
+                                img.paste(imgn, (0, 0), imgn)
+        except Exception:
+            traceback.print_exc()
+        print('get_bg exit')
+        time.sleep(3)
+
+def start_bg_task():
+    threading.Thread(target=get_bg, daemon=True).start()
+    while img is None:
+        time.sleep(1)
+    print('connection established')
+
+import random
+
+draw_seq = [(x, y) for x in range(X) for y in range(Y)]
+random.shuffle(draw_seq)
+start_bg_task()
+ldraw = Image.new(mode="RGBA", size=(X, Y))
+def draw(img):
+    global ldraw
+    send_icmp_q = []
+    start = time.time()
+    print('draw 1 frame in ', end='')
+    for x, y in draw_seq:
+        newpix = img.getpixel((x, y))
+        r, g, b, a = newpix
+        if a and newpix != ldraw.getpixel((x, y)):
+            send_icmp_q.append(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+    startsend = time.time()
+    send_icmp(send_icmp_q)
+    ldraw = img.copy()
+    end = time.time()
+    print(f"{1000*(end-start):.1f}ms {1000*(end-startsend):.1f}ms")
+
+ldraw = img.copy()
+draw(Image.open('1.png').convert('RGBA').resize((X, Y), Image.Resampling.LANCZOS))
+print('success')

gen1.py

@@ -0,0 +1,107 @@
+import struct
+class ICMP6:
+    _ICMP_ECHO_REQUEST       = 128
+    def __init__(self, destination, id, sequence, payload=None,
+            payload_size=56, ttl=64, traffic_class=0):
+
+        if payload is not None:
+            payload_size = len(payload)
+        else:
+            payload = b'\x00'*payload_size
+
+        self._destination = destination
+        self._id = id & 0xffff
+        self._sequence = sequence & 0xffff
+        self._payload = payload
+        self._payload_size = payload_size
+        self._ttl = ttl
+        self._traffic_class = traffic_class
+        self._time = 0
+    def _checksum(self, data):
+        '''
+        Compute the checksum of an ICMP packet. Checksums are used to
+        verify the integrity of packets.
+        '''
+        sum = 0
+        data += b'\x00'
+
+        for i in range(0, len(data) - 1, 2):
+            sum += (data[i] << 8) + data[i + 1]
+            sum  = (sum & 0xffff) + (sum >> 16)
+
+        sum = ~sum & 0xffff
+
+        return sum
+    def _create_packet(self):
+        '''
+        Build an ICMP packet from an identifier, a sequence number and
+        a payload.
+        This method returns the newly created ICMP header concatenated
+        to the payload passed in parameters.
+        '''
+        id, sequence, payload = self._id, self._sequence, self._payload
+        checksum = 0
+
+        # Temporary ICMP header to compute the checksum
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        checksum = self._checksum(header + payload)
+
+        # Definitive ICMP header
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        return header + payload
+
+
+
+
+
+X=512
+Y=512
+import socket, traceback, time
+import pathlib
+import json
+
+if pathlib.Path('1.png').exists():
+    from PIL import Image
+    img = Image.open('1.png')
+    img = img.resize((X, Y), Image.Resampling.LANCZOS)
+    img.save('out.png')
+    img = img.convert('RGBA')
+    imgd = []
+    for x in range(X):
+        imgd.append([])
+        for y in range(Y):
+            r, g, b, a = img.getpixel((x, y))
+            imgd[-1].append((r, g, b, a))
+#    with open('1.json', 'w') as f:
+#        json.dump(imgd, f)
+#    input('pil')
+else:
+    print('use 1.json')
+    with open('1.json', 'r') as f:
+        imgd = json.load(f)
+
+def send_icmp(addr):
+    try:
+        with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+            p = ICMP6(None, 0xad, 0, b'')._create_packet()
+            s.sendto(p, (addr, 0))
+    except Exception:
+       traceback.print_exc()
+
+import sys
+skip = int(sys.argv[1]) if sys.argv[1:] else 0
+slp = float(sys.argv[2]) if sys.argv[2:] else 0.0001
+for x in range(X):
+    if x < skip:
+        continue
+    print(f"{x=}")
+    for y in range(Y):
+        r, g, b, a = imgd[x][y]
+        if a:
+            send_icmp(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+            #print(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+            time.sleep(slp)

gen2.py

@@ -0,0 +1,162 @@
+import struct
+class ICMP6:
+    _ICMP_ECHO_REQUEST       = 128
+    def __init__(self, destination, id, sequence, payload=None,
+            payload_size=56, ttl=64, traffic_class=0):
+
+        if payload is not None:
+            payload_size = len(payload)
+        else:
+            payload = b'\x00'*payload_size
+
+        self._destination = destination
+        self._id = id & 0xffff
+        self._sequence = sequence & 0xffff
+        self._payload = payload
+        self._payload_size = payload_size
+        self._ttl = ttl
+        self._traffic_class = traffic_class
+        self._time = 0
+    def _checksum(self, data):
+        '''
+        Compute the checksum of an ICMP packet. Checksums are used to
+        verify the integrity of packets.
+        '''
+        sum = 0
+        data += b'\x00'
+
+        for i in range(0, len(data) - 1, 2):
+            sum += (data[i] << 8) + data[i + 1]
+            sum  = (sum & 0xffff) + (sum >> 16)
+
+        sum = ~sum & 0xffff
+
+        return sum
+    def _create_packet(self):
+        '''
+        Build an ICMP packet from an identifier, a sequence number and
+        a payload.
+        This method returns the newly created ICMP header concatenated
+        to the payload passed in parameters.
+        '''
+        id, sequence, payload = self._id, self._sequence, self._payload
+        checksum = 0
+
+        # Temporary ICMP header to compute the checksum
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        checksum = self._checksum(header + payload)
+
+        # Definitive ICMP header
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        return header + payload
+
+
+
+
+
+X=512
+Y=512
+import socket, traceback, time
+
+from PIL import Image, ImageOps
+img = Image.open('1.png')
+img = img.resize((X, Y), Image.Resampling.LANCZOS)
+img.save('out.png')
+img = img.convert('RGBA')
+
+imgdvd = Image.open('dvd.png')
+imgdvd = imgdvd.convert('RGBA')
+
+def send_icmp(addr):
+    try:
+        with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+            p = ICMP6(None, 0xad, 0, b'')._create_packet()
+            s.sendto(p, (addr, 0))
+    except Exception:
+       traceback.print_exc()
+
+import sys, random
+skip = int(sys.argv[1]) if sys.argv[1:] else 0
+slp = float(sys.argv[2]) if sys.argv[2:] else 0.0001
+slp1 = float(sys.argv[3]) if sys.argv[3:] else 0.5
+draw_img = int(sys.argv[4]) if sys.argv[4:] else 0
+
+Dx, Dy = imgdvd.size
+sx = random.randint(0, X-1-Dx)
+sy = random.randint(0, Y-1-Dy)
+fx = random.choice((1, -1))
+fy = random.choice((1, -1))
+
+def draw(img):
+    for x in range(X):
+        if x < skip:
+            continue
+        print(f"{x=}")
+        for y in range(Y):
+            r, g, b, a = img.getpixel((x, y))
+            if a:
+                send_icmp(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+                #print(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+                time.sleep(slp)
+
+D_RGB = [0, 0, 0]
+imgdvdc = None
+def update_drgb():
+    global imgdvdc
+    D_RGB.clear()
+    D_RGB.extend([random.randint(50, 250), random.randint(50, 250), random.randint(50, 250)])
+    imgdvdc = imgdvd.copy()
+    for x in range(Dx):
+        for y in range(Dy):
+            _, _, _, a = imgdvd.getpixel((x, y))
+            imgdvdc.putpixel((x, y), (*D_RGB, a))
+update_drgb()
+old1 = Image.new(mode="RGBA", size=(Dx, Dy))
+oldsxy = [0, 0]
+def blend():
+    global old1
+    new = img.crop((sx, sy, sx+Dx, sy+Dy))
+    old1_old = old1.copy()
+    #old1 = Image.new(mode="RGBA", size=(X, Y))
+    old1 = new.copy()
+    #old1.paste(old, (sx, sy))
+    new.paste(imgdvdc, (0, 0), imgdvdc)
+    new1 = Image.new(mode="RGBA", size=(X, Y))
+    #new1 = img.copy()
+    new1.paste(old1_old, oldsxy.copy(), old1_old)
+    new1.paste(new, (sx, sy), new)
+    oldsxy[0], oldsxy[1] = sx, sy
+    #new1.save('/tmp/2.png')
+    #time.sleep(0.5)
+    return new1
+
+STEP=5
+if draw_img:
+    draw(img)
+while True:
+    imgf = blend()
+    draw(imgf)
+
+    if fx > 0:
+        if sx + Dx >= X:
+            fx = -fx
+            update_drgb()
+    else:
+        if sx <= 0:
+            fx = -fx
+            update_drgb()
+    if fy > 0:
+        if sy + Dy >= Y:
+            fy = -fy
+            update_drgb()
+    else:
+        if sy <= 0:
+            fy = -fy
+            update_drgb()
+    sx += STEP * fx
+    sy += STEP * fy
+    time.sleep(slp1)

gen3.py

@@ -0,0 +1,281 @@
+import argparse
+parser = argparse.ArgumentParser()
+parser.add_argument('--skip', type=int, default=0, help="skip x lines (unused)")
+parser.add_argument('--drawfirst', action='store_true', help="draw image first (unused)")
+parser.add_argument('--slp', type=float, default=0.0001, help="sleep x seconds after each ping")
+parser.add_argument('--slp1', type=float, default=0.5, help="sleep x seconds after each frame")
+args = parser.parse_args()
+skip, slp, slp1, draw_img = args.skip, args.slp, args.slp1, args.drawfirst
+
+import struct
+class ICMP6:
+    _ICMP_ECHO_REQUEST       = 128
+    def __init__(self, destination, id, sequence, payload=None,
+            payload_size=56, ttl=64, traffic_class=0):
+
+        if payload is not None:
+            payload_size = len(payload)
+        else:
+            payload = b'\x00'*payload_size
+
+        self._destination = destination
+        self._id = id & 0xffff
+        self._sequence = sequence & 0xffff
+        self._payload = payload
+        self._payload_size = payload_size
+        self._ttl = ttl
+        self._traffic_class = traffic_class
+        self._time = 0
+    def _checksum(self, data):
+        '''
+        Compute the checksum of an ICMP packet. Checksums are used to
+        verify the integrity of packets.
+        '''
+        sum = 0
+        data += b'\x00'
+
+        for i in range(0, len(data) - 1, 2):
+            sum += (data[i] << 8) + data[i + 1]
+            sum  = (sum & 0xffff) + (sum >> 16)
+
+        sum = ~sum & 0xffff
+
+        return sum
+    def _create_packet(self):
+        '''
+        Build an ICMP packet from an identifier, a sequence number and
+        a payload.
+        This method returns the newly created ICMP header concatenated
+        to the payload passed in parameters.
+        '''
+        id, sequence, payload = self._id, self._sequence, self._payload
+        checksum = 0
+
+        # Temporary ICMP header to compute the checksum
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        checksum = self._checksum(header + payload)
+
+        # Definitive ICMP header
+        header = struct.pack('!2B3H', self._ICMP_ECHO_REQUEST, 0, checksum,
+            id, sequence)
+
+        return header + payload
+
+
+
+#import sys
+#skip = int(sys.argv[1]) if sys.argv[1:] else 0
+#slp = float(sys.argv[2]) if sys.argv[2:] else 0.0001
+#slp1 = float(sys.argv[3]) if sys.argv[3:] else 0.5
+#draw_img = int(sys.argv[4]) if sys.argv[4:] else 0
+
+X=512
+Y=512
+import socket, traceback, time
+
+from PIL import Image
+#img = Image.open('1.png')
+#img = img.resize((X, Y), Image.Resampling.LANCZOS)
+#img.save('out.png')
+#img = img.convert('RGBA')
+
+imgdvd = Image.open('dvd.png')
+imgdvd = imgdvd.convert('RGBA')
+
+icmp6pkt = ICMP6(None, 0xad, 0, b'')._create_packet()
+import concurrent.futures
+def send_icmp_mt(addrs, workers=10):
+    def sendto(addr):
+        with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+            s.sendto(icmp6pkt, (addr, 0))
+        time.sleep(slp)
+    with concurrent.futures.ThreadPoolExecutor(max_workers=workers) as executor:
+        for addr in addrs:
+            executor.submit(sendto, addr)
+        executor.shutdown(wait=True, cancel_futures=False)
+def send_icmp_st(addrs):
+    try:
+        for addr in addrs:
+            with socket.socket(socket.AF_INET6, socket.SOCK_DGRAM, socket.IPPROTO_ICMPV6) as s:
+                s.sendto(icmp6pkt, (addr, 0))
+            time.sleep(slp)
+    except Exception:
+       traceback.print_exc()
+send_icmp = send_icmp_st
+
+headers = {'User-Agent': 'curl/7.88.1)'}
+mkreq = lambda u: urllib.request.Request(u, data=None, headers=headers)
+timeout = 60
+
+import urllib.request
+import contextlib
+import base64
+import io
+import threading
+img = None
+imglock = threading.Lock()
+def get_bg():
+    global img
+    while True:
+        try:
+            with contextlib.closing(urllib.request.urlopen(mkreq('http://us2.g-load.eu:9090/stream'), timeout=timeout)) as resp:
+                for line in resp:
+                    if line.startswith(b'data:'):
+                        with imglock:
+                            imgn = Image.open(io.BytesIO(base64.b64decode(line[5:-1])))
+                            assert imgn.size == (X, Y)
+                            #print(imgn.mode)
+                            if img is None:
+                                img = imgn.convert(mode='RGBA')
+                            else:
+                                assert imgn.mode == 'RGBA'
+                                img.paste(imgn, (0, 0), imgn)
+        except Exception:
+            traceback.print_exc()
+        print('get_bg exit')
+        time.sleep(3)
+
+def start_bg_task():
+    threading.Thread(target=get_bg, daemon=True).start()
+    while img is None:
+        time.sleep(1)
+    print('connection established')
+
+import random
+
+Dx, Dy = imgdvd.size
+sx = random.randint(0, X-1-Dx)
+sy = random.randint(0, Y-1-Dy)
+fx = random.choice((1, -1))
+fy = random.choice((1, -1))
+
+#import numpy as np
+#draw_seq = np.arange(X*Y)
+#np.random.shuffle(draw_seq)
+
+#def _spr(rangex):
+#    maxidx = len(rangex) - 1
+#    ret = []
+#    mid = maxidx // 2
+#    dl = mid
+#    dr = mid
+#    ret.append(mid)
+#    while True:
+#        if dr < maxidx:
+#            dr += 1
+#            ret.append(dr)
+#        if dl > 0:
+#            dl -= 1
+#            ret.append(dl)
+#        if dl <= 0 and dr >= maxidx:
+#            assert len(ret) - 1 == maxidx
+#            return ret
+#draw_seq = [(i // X, i % X) for i in range(X*Y)]
+#draw_seq = [(x, y) for x in _spr(range(X)) for y in _spr(range(Y))]
+draw_seq = [(x, y) for x in range(X) for y in range(Y)]
+random.shuffle(draw_seq)
+start_bg_task()
+ldraw = Image.new(mode="RGBA", size=(X, Y))
+def draw(img):
+    global ldraw
+    send_icmp_q = []
+    start = time.time()
+    print('draw 1 frame in ', end='')
+    #for x in range(X):
+    for x, y in draw_seq:
+        #for y in range(Y):
+            #if x < skip:
+            #    continue
+        newpix = img.getpixel((x, y))
+        r, g, b, a = newpix
+        if a and newpix != ldraw.getpixel((x, y)):
+            send_icmp_q.append(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+            #print(f"fdcf:8538:9ad5:3333:{x:x}:{y:x}:11{r:02x}:{g:02x}{b:02x}")
+            #time.sleep(slp)
+    startsend = time.time()
+    send_icmp(send_icmp_q)
+    ldraw = img.copy()
+    end = time.time()
+    print(f"{1000*(end-start):.1f}ms {1000*(end-startsend):.1f}ms")
+
+ldraw = img.copy()
+draw(Image.open('1.png').convert('RGBA').resize((X, Y), Image.Resampling.LANCZOS))
+print('success')
+exit(0)
+
+D_RGB = [0, 0, 0]
+imgdvdc = None
+def update_drgb():
+    global imgdvdc
+    D_RGB.clear()
+    D_RGB.extend([random.randint(50, 250), random.randint(50, 250), random.randint(50, 250)])
+    imgdvdc = imgdvd.copy()
+    for x in range(Dx):
+        for y in range(Dy):
+            _, _, _, a = imgdvd.getpixel((x, y))
+            imgdvdc.putpixel((x, y), (*D_RGB, a))
+update_drgb()
+import collections
+oldn = collections.deque()
+for _ in range(5):
+    oldn.append(((0, 0), Image.new(mode="RGBA", size=(Dx, Dy))))
+assert len(oldn) >= 3
+def blend(doexit=False):
+    global img
+    with imglock:
+        for old1 in oldn:
+            img.paste(old1[1], old1[0], old1[1])
+        new = img.crop((sx, sy, sx+Dx, sy+Dy))
+    oldn.append(((sx, sy), new.copy()))
+    oldn.popleft()
+    new.paste(imgdvdc, (0, 0), imgdvdc)
+    new1 = Image.new(mode="RGBA", size=(X, Y))
+    #new1 = img.copy()
+    old2 = oldn[-2]
+    new1.paste(old2[1], old2[0], old2[1])
+    if doexit:
+        old3 = oldn[-3]
+        new1.paste(old3[1], old3[0], old3[1])
+        return new1
+    new1.paste(new, (sx, sy), new)
+    #new1.save('/tmp/2.png')
+    #time.sleep(0.5)
+    return new1
+
+STEP=5
+#if draw_img:
+#    draw(img)
+try:
+    while True:
+        draw(blend())
+
+        if fx > 0:
+            if sx + Dx >= X:
+                fx = -fx
+                update_drgb()
+        else:
+            if sx <= 0:
+                fx = -fx
+                update_drgb()
+        if fy > 0:
+            if sy + Dy >= Y:
+                fy = -fy
+                update_drgb()
+        else:
+            if sy <= 0:
+                fy = -fy
+                update_drgb()
+        sx += STEP * fx
+        sy += STEP * fy
+        sx = sx if sx >= 0 else 0
+        sx = sx if sx + Dx < X else X - Dx
+        sy = sy if sy >= 0 else 0
+        sy = sy if sy + Dy < Y else Y - Dy
+        time.sleep(slp1)
+except KeyboardInterrupt:
+    print('exit...')
+    ldraw = Image.new(mode="RGBA", size=(X, Y))
+    draw(blend(doexit=True))
+    time.sleep(1)