**Used version**
v1.6.0-637 (latest at the moment)

**Scenario**
Use mp4-dash.py util to generate Smooth Streaming compatible output by specifying `--smooth`.

**Problem description**
The track name in the audio URL template of the generated .ismc file mismatches the track name in the generated .ism file.

Example audio URL template and the audio portion in the corresponding .ism file:
```
// URL template in .ismc
QualityLevels({bitrate})/Fragments(English={start time})
```
```
// Audio portion in the corresponding .ism
<audio src="tears_audio_eng.mp4" systemBitrate="136075">
    <param name="trackID" value="1" valueType="data"/>
    <param name="trackName" value="audio_en" valueType="data"/>
    <param name="timeScale" value="44100" valueType="data"/>
</audio>
```
The track name in the .ismc file `English` is supposed to match the one in the .ism file `audio_en`.

**Cause**
It seems it's introduced here:
https://github.com/axiomatic-systems/Bento4/commit/4916daf0#diff-e47888547647a4f042e89b39ca9f3db16ff8ec57ae8bf7eed250d050c6139061L1007

**Possible fix**
```
diff --git a/Source/Python/utils/mp4-dash.py b/Source/Python/utils/mp4-dash.py
index a9234b1..ce398d3 100755
--- a/Source/Python/utils/mp4-dash.py
+++ b/Source/Python/utils/mp4-dash.py
@@ -1026,7 +1026,7 @@ def OutputSmooth(options, audio_tracks, video_tracks):
             stream_name = audio_track.language_name
         if stream_name == '' or stream_name == 'Unknown':
             stream_name = "audio_"+audio_track.language
-        audio_url_pattern="QualityLevels({bitrate})/Fragments(%s={start time})" % (stream_name)
+        audio_url_pattern="QualityLevels({bitrate})/Fragments(audio_%s={start time})" % (audio_track.language)
         stream_index = xml.SubElement(client_manifest,
                                       'StreamIndex',
                                       Chunks=str(len(audio_track.moofs)),
```
Mismatch of audio track name between generated smooth client and server manifest
This is a GitHub Issue
repo:Bento4
owner:axiomatic-systems
Title : Mismatch of audio track name between generated smooth client and server manifest
Issue date:

--- start body ---
**Used version**
v1.6.0-637 (latest at the moment)

**Scenario**
Use mp4-dash.py util to generate Smooth Streaming compatible output by specifying `--smooth`.

**Problem description**
The track name in the audio URL template of the generated .ismc file mismatches the track name in the generated .ism file.

Example audio URL template and the audio portion in the corresponding .ism file:
```
// URL template in .ismc
QualityLevels({bitrate})/Fragments(English={start time})
```
```
// Audio portion in the corresponding .ism
<audio src="tears_audio_eng.mp4" systemBitrate="136075">
    <param name="trackID" value="1" valueType="data"/>
    <param name="trackName" value="audio_en" valueType="data"/>
    <param name="timeScale" value="44100" valueType="data"/>
</audio>
```
The track name in the .ismc file `English` is supposed to match the one in the .ism file `audio_en`.

**Cause**
It seems it's introduced here:
https://github.com/axiomatic-systems/Bento4/commit/4916daf0#diff-e47888547647a4f042e89b39ca9f3db16ff8ec57ae8bf7eed250d050c6139061L1007

**Possible fix**
```
diff --git a/Source/Python/utils/mp4-dash.py b/Source/Python/utils/mp4-dash.py
index a9234b1..ce398d3 100755
--- a/Source/Python/utils/mp4-dash.py
+++ b/Source/Python/utils/mp4-dash.py
@@ -1026,7 +1026,7 @@ def OutputSmooth(options, audio_tracks, video_tracks):
             stream_name = audio_track.language_name
         if stream_name == '' or stream_name == 'Unknown':
             stream_name = "audio_"+audio_track.language
-        audio_url_pattern="QualityLevels({bitrate})/Fragments(%s={start time})" % (stream_name)
+        audio_url_pattern="QualityLevels({bitrate})/Fragments(audio_%s={start time})" % (audio_track.language)
         stream_index = xml.SubElement(client_manifest,
                                       'StreamIndex',
                                       Chunks=str(len(audio_track.moofs)),
```
--- end body ---
