diff --git a/src/extract_rdcosts.py b/src/extract_rdcosts.py
index 02145ede..825ba2f3 100755
--- a/src/extract_rdcosts.py
+++ b/src/extract_rdcosts.py
@@ -1,6 +1,7 @@
 #!/usr/bin/env python3
 
 import glob
+import gzip
 import os
 import subprocess
 import threading
@@ -12,14 +13,52 @@ ofdir  = os.path.join("/tmp", "rdcost", "data")
 n_threads   = 8
 home_rel    = lambda path: os.path.join(os.environ["HOME"], path)
 
-qps         = range(12, 14)
-sequences   = ("/opt/test_seqs/hevc-B/*.yuv",)
+dest_qps    = tuple(range(51))
+base_qps    = tuple(range(12, 43))
+#base_qps    = tuple(range(12, 15))
+sequences   = ("/opt/test_seqs/hevc-B/*.yuv", "/opt/test_seqs/custom_seqs/*/*.yuv")
+#sequences   = ("/opt/test_seqs/custom_seqs/*/*.yuv",)
 
-kvzargs     = [home_rel("kvazaar/src/kvazaar"), "--threads", "1", "--preset=ultrafast"]
+kvzargs     = [home_rel("kvazaar/src/kvazaar"), "--threads", "1", "--preset=ultrafast", "--fastrd-sampling", "--fast-residual-cost=0"]
 kvzenv      = {"LD_LIBRARY_PATH": home_rel("kvazaar/src/.libs/")}
 
 gzargs      = ["gzip"]
 
+class MultiPipeGZOutManager:
+    pipe_fn_template  = "%02i.txt"
+    gzout_fn_template = "%02i.txt.gz"
+
+    def __init__(self, odpath, dest_qps):
+        self.odpath = odpath
+        self.dest_qps = dest_qps
+
+        self.pipe_fns  = []
+        self.gzout_fns = []
+        for qp in dest_qps:
+            pipe_fn  = os.path.join(self.odpath, self.pipe_fn_template % qp)
+            gzout_fn = os.path.join(self.odpath, self.gzout_fn_template % qp)
+
+            self.pipe_fns.append(pipe_fn)
+            self.gzout_fns.append(gzout_fn)
+
+    def __enter__(self):
+        os.makedirs(self.odpath, exist_ok=True)
+        for pipe_fn in self.pipe_fns:
+            try:
+                os.unlink(pipe_fn)
+            except FileNotFoundError:
+                pass
+            os.mkfifo(pipe_fn)
+        return self
+
+    def __exit__(self, *_):
+        for pipe_fn in self.pipe_fns:
+            os.unlink(pipe_fn)
+
+    def items(self):
+        for pipe_fn, gzout_fn in zip(self.pipe_fns, self.gzout_fns):
+            yield (pipe_fn, gzout_fn)
+
 class MTSafeIterable:
     def __init__(self, iterable):
         self.lock = threading.Lock()
@@ -42,6 +81,26 @@ def chain(lol):
         for i in l:
             yield i
 
+# Would've used Popen with gzip, but "gzip [fifo]" with an unconnected fifo
+# will detect the situation and not block, but just consider it an empty
+# file. Don't like it when tools outsmart their user..
+def do_gzip(in_fn, out_fn):
+    BLOCK_SZ = 65536
+    PRINT_MULT = 1024
+    with open(in_fn, "rb") as inf, gzip.open(out_fn, "wb") as outf:
+        num_read = 0
+        print_next_thres = BLOCK_SZ * PRINT_MULT
+        while True:
+            block = inf.read(BLOCK_SZ)
+            num_read += len(block)
+            if (num_read >= print_next_thres):
+                print("    read %8i MB from %s" % (num_read / (1024 * 1024), in_fn))
+                print_next_thres += BLOCK_SZ * PRINT_MULT
+
+            if (len(block) == 0):
+                break
+            outf.write(block)
+
 def run_job(job):
     ifpath, qp = job
     ifname = os.path.basename(ifpath)
@@ -49,30 +108,45 @@ def run_job(job):
     jobname  = "%s-qp%i" % (ifname, qp)
     hevcname = "%s.hevc" % jobname
     logname  = "%s.log"  % jobname
-    ofname   = "%s.gz"   % jobname
+    odname   = jobname
 
     hevcpath = os.path.join("/tmp", hevcname)
     logpath  = os.path.join(logdir, logname)
-    ofpath   = os.path.join(ofdir,  ofname)
+    odpath   = os.path.join(ofdir,  odname)
 
-    my_kvzargs = kvzargs + ["-i",   ifpath,
-                            "--qp", str(qp),
-                            "-o",   hevcpath]
+    my_kvzargs = kvzargs + ["-i",              ifpath,
+                            "--qp",            str(qp),
+                            "-o",              hevcpath,
+                            "--fastrd-outdir", odpath]
 
     with open(logpath, "w") as lf:
-        with open(ofpath, "wb") as of:
-            kvz = subprocess.Popen(my_kvzargs, env=kvzenv, stdout=subprocess.PIPE, stderr=lf)
-            gzip = subprocess.Popen(gzargs, stdin=kvz.stdout, stdout=of)
+        with MultiPipeGZOutManager(odpath, dest_qps) as pipes_and_outputs:
+            gzips = []
+            gzip_threads = []
+            #for pipe_fn, out_f in pipes_and_outputs.items():
+            for pipe_fn, out_fn in pipes_and_outputs.items():
+                #my_gzargs = gzargs + ["-c", pipe_fn]
+                #gzip = subprocess.Popen(my_gzargs, stdout=out_f)
+                #gzips.append(gzip)
+                #print("  launched gzip %s" % " ".join(my_gzargs))
+
+
+                gzip_thread = threading.Thread(target=do_gzip, args=(pipe_fn, out_fn))
+                gzip_thread.start()
+                gzip_threads.append(gzip_thread)
+
+            kvz = subprocess.Popen(my_kvzargs, env=kvzenv, stderr=lf)
 
-            gzip.communicate()
             kvz.communicate()
+            for gzip in gzips:
+                gzip.communicate()
 
 def threadfunc(joblist):
     for job in joblist:
         run_job(job)
 
 def main():
-    jobs = combinations(chain(map(glob.glob, sequences)), qps)
+    jobs = combinations(chain(map(glob.glob, sequences)), base_qps)
     joblist = MTSafeIterable(jobs)
 
     threads = [threading.Thread(target=threadfunc, args=(joblist,)) for _ in range(n_threads)]