style cleaning

Added "streamhash" recipe.

index.html

@@ -1867,7 +1867,7 @@
         <dt>$output</dt><dd>The output file is set to the value of the <code>$output</code> variable declared above: i.e., the current file name with an .mkv extension.</dd>
         <dt>}</dt><dd>Closes the code block.</dd>
       </dl>
-      <p><strong>Note:</strong> the PowerShell script (.ps1 file) and all .mp4 files to be rewrapped must be contained within the same directory, and the script must be run from that directory.<p>
+      <p><strong>Note:</strong> the PowerShell script (.ps1 file) and all .mp4 files to be rewrapped must be contained within the same directory, and the script must be run from that directory.</p>
       <p>Execute the .ps1 file by typing <code>.\rewrap-mp4.ps1</code> in PowerShell.</p>
       <p>Modify the script as needed to perform different transcodes, or to use with ffprobe. :)</p>
       <p class="link"></p>
@@ -1997,6 +1997,33 @@
     </div>
     <!-- ends Get checksum for video/audio stream -->
 
+    <!-- Get checksum for all video/audio streams -->
+    <label class="recipe" for="get_streamhash">Get individual checksums for all video/audio streams ("Streamhash")</label>
+    <input type="checkbox" id="get_streamhash">
+    <div class="hiding">
+      <h5>Get individual checksums for all video/audio streams ("Streamhash")</h5>
+      <p><code>ffmpeg -i <em>input_file</em> -map 0 -f streamhash -hash md5 - -v quiet</code></p>
+      <p>The outcome is very similar to that of "-f hash", except you get one hash per-stream, instead of one (summary) hash. Another benefit is that you don't have to know which streams, or how many to expect in the source file. This is very handy for hashing mixed born-digital material.</p>
+      <p>This script will perform a fixity check on all audio and video streams in the file and return one hashcode for each one.  This is useful for e.g. being able to change to container/codec format later on and validate it matches the original source.</p>
+      <p>The output is formatted for easily processing it further in any kind of programming/scripting language.</p>
+      <dl>
+        <dt>ffmpeg</dt><dd>starts the command</dd>
+        <dt>-i <em>input_file</em></dt><dd>path, name and extension of the input file</dd>
+        <dt>-map 0</dt><dd>map ALL streams from input file to output. If you omit this, ffmpeg chooses only the first "best" (*) stream: 1 for audio, 1 for video (not all streams).</dd>
+        <dt>-f streamhash -hash md5</dt><dd>produce a checksum hash per-stream, and set the hash algorithm to md5. See the official <a href="https://www.ffmpeg.org/ffmpeg-formats.html#streamhash-1" target="_blank">documentation on streamhash</a> for other algorithms and more details.</dd>
+        <dt>-</dt><dd>FFmpeg syntax requires a specified output, and <code>-</code> is just a place holder. No file is actually created. Choose an output filename to write the hashcode lines into a textfile.</dd>
+        <dt>-v quiet</dt><dd>(Optional) Disables FFmpeg's processing output. With this option it's easier to see the text output of the hashes.</dd>
+      </dl>
+      <p>The output looks like this, for example (1 video, 2 audio streams):
+      <code>
+      0,v,MD5=89bed8031048d985b48550b6b4cb171c<br>
+      0,a,MD5=36daadb543b63610f63f9dcff11680fb<br>
+      1,a,MD5=f21269116a847f887710cfc67ecc3e6e
+      </code></p>
+      <p class="link"></p>
+    </div>
+    <!-- ends Get checksum for all video/audio streams -->
+
     <!-- QCTools Report -->
     <label class="recipe" for="qctools">QCTools report (with audio)</label>
     <input type="checkbox" id="qctools">

recipes.txt

@@ -141,6 +141,8 @@ ffmpeg -i input_file -af "asetnsamples=n=48000" -f framemd5 -vn output_file
 ffmpeg -i input_file -map 0:v:0 -c:v copy -f md5 output_file_1 -map 0:a:0 -c:a copy -f md5 output_file_2
 # Get checksum for video/audio stream
 ffmpeg -loglevel error -i input_file -map 0:v:0 -f hash -hash md5 -
+# Get individual checksums for all video/audio streams ("Streamhash")
+ffmpeg -i input_file -map 0 -f streamhash -hash md5 - -v quiet
 # QCTools report (with audio)
 ffprobe -f lavfi -i "movie=input_file:s=v+a[in0][in1], [in0]signalstats=stat=tout+vrep+brng, cropdetect=reset=1:round=1, idet=half_life=1, split[a][b];[a]field=top[a1];[b]field=bottom, split[b1][b2];[a1][b1]psnr[c1];[c1][b2]ssim[out0];[in1]ebur128=metadata=1, astats=metadata=1:reset=1:length=0.4[out1]" -show_frames -show_versions -of xml=x=1:q=1 -noprivate | gzip > input_file.qctools.xml.gz
 # QCTools report (no audio)