I have encountered three cases where argument parsing is different than what I expected. Let me know if I wrote the arguments incorrectly.

> Note that RSID and indexes were intentionally removed from the resulting graph output

## Example 1

**Command Line**
```
gpac -np fin:src=video.mp4:RSID @ vcrop:wnd=0x0 vflip:RSID @@0 vcrop:wnd=0x0 vflip:RSID @@2#V1 @#V1 mp4mx fout:dst=output.mp4 @@4#V1 probe @@4#V1 vout -graph
```

**Resulting graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip
-----(PID V1) mp4mx
------(PID V1) fout (dst=output.mp4)
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip (wnd=0x0)
-----(PID V1) mp4mx
Filters not connected:
vflip
probe
Filters in unknown connection state:
vout
```

**Expected graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip
-----(PID V1) mp4mx
------(PID V1) fout (dst=output.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip
-----(PID V1) probe
-----(PID V1) mp4mx
-----(PID V1) vout
```

## Example 2

**Command Line**
```
gpac -np fin:src=video.mp4:RSID @ vflip fout:dst=output.mp4 -graph
```

**Resulting graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vflip
----(PID V1) mp4mx
Filters not connected:
fout (dst=output.mp4)
```

**Expected graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vflip
----(PID V1) mp4mx
-----(PID V1) fout (dst=output.mp4)
```

## Example 3

**Command Line**
```
gpac -np fin:src=video.mp4:RSID fin:src=audio.wav @@0 @ mp4mx fout:dst=output.mp4 -graph
```

**Resulting graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1)\
--(PID A2)-> mp4mx
---(PID isobmf_mux) fout (dst=output.mp4)
fin (src=audio.wav)
-(PID audio.wav) rfpcm
--(PID audio.wav) mp4mx
-(PID audio.wav) rfpcm
--(PID audio.wav) mp4mx
Filters not connected:
mp4mx
```

**Expected graph output**
```
Filters connected:
fin (src=audio.wav)
-(PID audio.wav) rfpcm
--(PID audio.wav) mp4mx
---(PID isobmf_mux) fout (dst=output.mp4)
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1)\
--(PID A2)-> mp4mx
```
Argument parsing is incorrect on some cases
This is a GitHub Issue
repo:gpac
owner:gpac
Title : Argument parsing is incorrect on some cases
Issue date:

--- start body ---
I have encountered three cases where argument parsing is different than what I expected. Let me know if I wrote the arguments incorrectly.

> Note that RSID and indexes were intentionally removed from the resulting graph output

## Example 1

**Command Line**
```
gpac -np fin:src=video.mp4:RSID @ vcrop:wnd=0x0 vflip:RSID @@0 vcrop:wnd=0x0 vflip:RSID @@2#V1 @#V1 mp4mx fout:dst=output.mp4 @@4#V1 probe @@4#V1 vout -graph
```

**Resulting graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip
-----(PID V1) mp4mx
------(PID V1) fout (dst=output.mp4)
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip (wnd=0x0)
-----(PID V1) mp4mx
Filters not connected:
vflip
probe
Filters in unknown connection state:
vout
```

**Expected graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip
-----(PID V1) mp4mx
------(PID V1) fout (dst=output.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vcrop (wnd=0x0)
----(PID V1) vflip
-----(PID V1) probe
-----(PID V1) mp4mx
-----(PID V1) vout
```

## Example 2

**Command Line**
```
gpac -np fin:src=video.mp4:RSID @ vflip fout:dst=output.mp4 -graph
```

**Resulting graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vflip
----(PID V1) mp4mx
Filters not connected:
fout (dst=output.mp4)
```

**Expected graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1) wcdec
---(PID V1) vflip
----(PID V1) mp4mx
-----(PID V1) fout (dst=output.mp4)
```

## Example 3

**Command Line**
```
gpac -np fin:src=video.mp4:RSID fin:src=audio.wav @@0 @ mp4mx fout:dst=output.mp4 -graph
```

**Resulting graph output**
```
Filters connected:
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1)\
--(PID A2)-> mp4mx
---(PID isobmf_mux) fout (dst=output.mp4)
fin (src=audio.wav)
-(PID audio.wav) rfpcm
--(PID audio.wav) mp4mx
-(PID audio.wav) rfpcm
--(PID audio.wav) mp4mx
Filters not connected:
mp4mx
```

**Expected graph output**
```
Filters connected:
fin (src=audio.wav)
-(PID audio.wav) rfpcm
--(PID audio.wav) mp4mx
---(PID isobmf_mux) fout (dst=output.mp4)
fin (src=video.mp4)
-(PID video.mp4) mp4dmx
--(PID V1)\
--(PID A2)-> mp4mx
```
--- end body ---
