chunked content script - see cta-wave/Test-Content#41

README.md

@@ -56,6 +56,10 @@ cd ..
   * Inspect the [input list](switching_sets_single_track.csv).
 * Run ```./run-all.py```, and grab a cup of tea (or coffee).
 
+### Switching Set X1 (ss1)
+
+The generation of current [Switching Set X1 (ss1)](https://github.com/cta-wave/Test-Content-Generation/issues/60) is done by executing ```ss1/gen.sh```
+
 ### Splicing tests
 
 The generation of current [splicing tests](https://github.com/cta-wave/Test-Content/issues/19) is done by executing ```splice/gen.sh ```.

chunked/gen.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/bash
+set -eux
+
+export BATCH="2023-04-28"
+
+export MPD=stream.mpd
+export INPUT_STREAM_ID=t16
+export INPUT_DIR=output/cfhd_sets/12.5_25_50/$INPUT_STREAM_ID/$BATCH/
+export OUTPUT_STREAM_ID=chunked
+export OUTPUT=chunked
+export OUTPUT_DIR=output/cfhd_sets/12.5_25_50/$OUTPUT_STREAM_ID/$BATCH/
+
+
+# clean copy of input
+mkdir -p $OUTPUT_DIR
+rm -rf $OUTPUT_DIR/*
+cp -r $INPUT_DIR/* $OUTPUT_DIR/
+
+
+#######################################################
+# chunking
+pushd $OUTPUT_DIR/1
+
+## styp generation: take it from the first segment
+head -c12 0.m4s > styp
+
+## chunk segments
+for f in `ls *.m4s`; do
+    $(dirname $0)/isobmff_chunker.py 5 `basename $f .m4s`
+    rm $f
+done
+
+rm styp
+
+## modify MPD
+cp $(dirname $0)/stream.mpd ../stream.mpd
+
+popd
+#######################################################
+
+# zip
+pushd output
+rm cfhd_sets/12.5_25_50/$OUTPUT_STREAM_ID/$BATCH/$INPUT_STREAM_ID.zip
+zip -r cfhd_sets/12.5_25_50/$OUTPUT_STREAM_ID/$BATCH/$OUTPUT_STREAM_ID.zip cfhd_sets/12.5_25_50/$OUTPUT_STREAM_ID/$BATCH/*
+popd

chunked/isobmff_chunker.py

@@ -0,0 +1,96 @@
+#!/usr/bin/env python3
+import sys
+import struct
+
+def read_bytes(fobj, bytes):
+    data = fobj.read(bytes)
+    if len(data) != bytes:
+        raise RuntimeError('Not enough data: requested %d, read %d' % (bytes, len(data)))
+    return data
+
+def read_ulong(fobj):
+    return struct.unpack('>L', read_bytes(fobj, 4))[0]
+
+def read_ulonglong(fobj):
+    return struct.unpack('>Q', read_bytes(fobj, 8))[0]
+
+def read_fourcc(fobj):
+    return read_bytes(fobj, 4)
+
+def read_atom(fobj):
+    pos = fobj.tell()
+    size = read_ulong(fobj)
+    type = read_fourcc(fobj)
+
+    if size == 1:
+        size = read_ulonglong(fobj)
+    elif size == 0:
+        fobj.seek(0, 2)
+        size = fobj.tell() - pos
+        fobj.seek(pos + 8)
+
+    return size, type
+
+def isobmff_read_topboxes(f):
+    size = 0
+    f.seek(0)
+    pos = 0
+    f.seek(0, 2)
+    end = f.tell()
+    f.seek(0)
+
+    result = []
+    while 1:
+        if pos + size < end:
+            pos += size
+            f.seek(pos)
+            a = read_atom(f)
+            result.append(a)
+            size = a[0]
+        else:
+            break
+
+    return result
+
+if __name__ == "__main__":
+    if len(sys.argv) != 3:
+        print(f"Usage: {sys.argv[0]} num_frag_per_chunk input_file")
+        sys.exit(1)
+
+    num_frag_per_chunk = int(sys.argv[1])
+    input_file = sys.argv[2]
+
+    # open and parse
+    fi = open(input_file + ".m4s", 'rb')
+    boxes = isobmff_read_topboxes(fi)
+    fi.seek(0)
+
+    # iterate on boxes
+    i_moof = -1
+    i_chunk = -1
+    global fo
+    fo = None
+    for b in boxes:
+        bytes = fi.read(b[0]);
+        if b[1] == b'styp':
+            continue
+
+        if b[1] == b'moof':
+            i_moof += 1
+
+        if i_moof % num_frag_per_chunk == 0 and i_moof / num_frag_per_chunk != i_chunk:
+            # new chunk
+            if fo is not None:
+                fo.close()
+            i_chunk += 1
+            fo = open(input_file + "_" + str(i_chunk) + ".m4s", 'wb')
+            styp = open("styp", 'rb')
+            fo.write(styp.read(12))
+            styp.close();
+
+        fo.write(bytes)
+
+    # close
+    fo.close()
+    fi.close()
+    sys.exit(0)

chunked/stream.mpd

@@ -0,0 +1,20 @@
+<?xml version="1.0" ?>
+<!-- MPD file Generated with GPAC version 2.3-DEV-rev222-g4c2ad897f-ffenc_timescale_cbr at 2023-04-29T11:15:38.134Z -->
+<MPD xmlns="urn:mpeg:dash:schema:mpd:2011" minBufferTime="PT2.000S" type="static" mediaPresentationDuration="PT0H0M30.000S" maxSegmentDuration="PT0H0M2.000S" profiles="urn:mpeg:dash:profile:isoff-live:2011,urn:mpeg:dash:profile:cmaf:2019,urn:cta:wave:test-content-media-profile:2022">
+  <ProgramInformation>
+    <Title>croatia, 1920x1080, 25.0fps, cfhd, Test Vector 16</Title>
+    <Source>croatia_L1_1920x1080@25_30 version 4 (2023-02-13)</Source>
+    <Copyright>© Croatia (2019), credited to EBU, used and licensed under Creative Commons Attribution 4.0 International (CC BY 4.0) (https://creativecommons.org/licenses/by/4.0/) by the Consumer Technology Association (CTA)® / annotated, encoded and compressed from original.</Copyright>
+  </ProgramInformation>
+  <Period duration="PT0H0M30.000S">
+    <AdaptationSet segmentAlignment="true" maxWidth="1920" maxHeight="1080" maxFrameRate="25" par="16:9" lang="und" startWithSAP="1" subsegmentAlignment="true" subsegmentStartsWithSAP="1" contentType="video" containerProfiles="cmf2 cfhd">
+      <SegmentTemplate media="1/$Time$_$SubNumber$.m4s" initialization="1/init.mp4" timescale="12800">
+        <SegmentTimeline>
+          <S t="0" d="25600" k="2" r="14"/>
+        </SegmentTimeline>
+      </SegmentTemplate>
+      <Representation id="1" mimeType="video/mp4" codecs="avc1.640028" width="1920" height="1080" frameRate="25" sar="1:1" bandwidth="4600000">
+   </Representation>
+    </AdaptationSet>
+  </Period>
+</MPD>