Can anyone identify the military branch and rank of the man in the front row? This is from Germany @1932

It is not an Imperial, Weimar, or Third Reich naval uniform.

It does, however, appear to be a Weimar period reichsbahn (railroad) police uniform . . .

Some discussion in a collectors' forum here https://www.warrelics.eu/forum/weimar-soft-headgear/reichsbahn-headgear-368798/ several shots of this type uniform on the second page of the discussion thread.

If this is the relevant person:

(click to enlarge pictures)

then the actual salient points are:

• cap: 'flying/winged wheels', double c**kade -> Reichsbahn employee

• shoulderboards to be expected as usual rank insignia: later than this timeframe, thus absent in this picture

• before 1935: rank & section/specialty on display in gorget patches

What is there visible in gorget patches?

Apparently one square pip and a circular symbol.

The most comprehensive book on this displays them in hi-res as such:

— Hartmut Schöttge: "Eisenbahner Uniform Reichsbahn 1924 bis 1934", Delitzsch: Schöttge, 2007.

Thus a table to compare these insignia would be:

and in combination with

Which to my eyes on this grainy picture gives a level 4 employee in the field of construction:

1. “Double-winged wheel” (Carriage service). Conductor (Zugschaffner – 15), senior conductor (Oberzugschaffner – 15), trainmaster (Zugführer – 10), senior trainmaster (Oberzugführer – 9а), luggage guard (Fahrladeschaffner – 15), senior luggage guard (Fahrladeoberschaffner – 15), motor coach conductor (Triebwagenschaffner – 15), motor coach senior conductor (Triebwagenoberschaffner – 15).

2. “Winged wheel with three lightning bolts” (Motor coach service). Motor coach supervisor (Triebwagenführer – 13), motor coach senior supervisor (Obertriebwagenführer – 13).

3. “Track gage with support” (Track maintenance service). Headman (Rottenführer – 15), senior headman (Oberrottenführer – 15), section gang foreman (Rottenmeister – 12), section gang senior foreman (Oberrottenmeister – 9a).

4. “Wheel with superimposed letter R” (Shunting service). Shunting supervisor (Rangieraufseher – 15), shunting controller (Rangiermeister – 12), senior shunting controller (Oberrangiermeister – 9а).

5. “Two crossed lightning bolts” (Power supply service). Railway communication network warden (Leitungsaufseher – 15), railway communication network senior warden (Leitungsoberaufseher – 15), railway communication network controller (Leitungsmeister – 12), railway communication network senior controller (Oberleitungsmeister – 9а), railway signalling operator (Signalwerkführer – 11), signal tower station senior operator (Oberwerkführer für Stellwerke – 9а), railway signalling foreman (Signalwerkmeister – 9), railway telegraphist (Telegrafenwerkführer – 11), railway telegraph operator (Telegrafenwerkmeister – 9), railway maintenance inspector of Telegraph service (technischer Reichsbahninspektor im Telegrafenwerkstättendienst – 7), railway maintenance senior inspector of Telegraph service (technischer Reichsbahnoberinspektor im Telegrafenwerkstättendienst – 6), railway administrator of Telegraph service (Reichsbahnamtmann im Telegrafenwerkstättendienst – 5).

6. “Coach” (Passenger car service). Coach warden (Wagenaufseher – 14), coach mechanical engineer (Wagenmeister – 11), coach senior mechanical engineer (Oberwagenmeister – 9а), coach foreman (Wagenwerkmeister – 9).

7. “Steam locomotive” (Locomotive operational service). Steam locomotive fireman (Lokomotivheizer – 13), Senior steam locomotive fireman (Oberlokomotivheizer – 13), reserve locomotive driver (Reservelokomotivführer – 11), locomotive driver (Lokomotivführer – 9), senior locomotive driver (Oberlokomotivführer – 7а).

8. “Gear with three lightning bolts” (Electrotechnical service). Senior machinist (Obermaschinist – 14а), mechanical engineer (Werkführer – 11), depot mechanical engineer (Betriebswerkführer – 11), foreman (Werkmeister – 9), depot foreman (Betriebswerkmeister – 9), depot senior foreman (Betriebsoberwerkmeister – 7а), railway power-stations and power supply maintenance inspector (technischer Reichsbahninspektor für Kraftwerke (Elektrizitätswerke) und Unterhaltung elektrischer Leitungsnetze – 7), railway power-stations and power supply maintenance senior inspector (technischer Reichsbahnoberinspektor für Kraftwerke (Elektrizitätswerke) und Unterhaltung elektrischer Leitungsnetze – 6), railway power-stations and power supply maintenance administrator (Reichsbahnamtmann für Kraftwerke (Elektrizitätswerke) und Unterhaltung elektrischer Leitungsnetze – 5).

9. “Wheel with compass” (Construction service). Railway maintenance inspector of Construction service (technischer Reichsbahninspektor im bautechnischen Außendienst – 7), railway maintenance senior inspector of Construction service (technischer Reichsbahnoberinspektor im bautechnischen Außendienst – 6), railway administrator of Construction service (Reichsbahnamtmann im bautechnischen Außendienst – 5).

10. “Motor car” (Cargo and passenger traffic service). High-speed omnibus driver (Fahrer der Schnellreisewagen), public cargo truck driver (Fahrer des Lastkraftwagen für den öffentlichen Güterverkehr), public cargo truck driver assistant (Begleiter des Lastkraftwagen für den öffentlichen Güterverkehr). Correspondence of positions to a schedule of charges of German Imperial Railways for those employees was flexible.
    — Specialist patches of German Imperial Railways (1935-1941) (slightly anachronistic)

The above garphical table is slightly a mismatch for the exact date, being a tiny bit too late. But a manufacturer for uniforms listed this kind of isignia for the desired timeframe also as

— Spartenabzeichen Eisenbahn/Reichsbahn, 1924 (Uniform, Rangabzeichen)

So we seem to have to differentiate mainly between two insignia:

To me, it looks less like an "R" in dense pixels, but more like compass on a lighter ground.

Combing L4 with section 9.

Making it a bahnmeister.

This is a Railway (Reichsbahn) uniform from the period 1924 until June 1935.

The rank is probably Rangieraufseher (Shunting supervisor).

Ranks, 1924-1935-06	Railway Cap, 1924-1935-06

Source:

• Reichsbahn Headgear
• Rangabzeichen nach der Dienstkleiderordnung (DKO) 1924
• DPSG Kluft 1930-1939

Wolfskopf (1930-1960)
May be the symbol seen on the 2nd person from the left.