Add support for audio queries: fix permissions on SoundRaw* + add ata…

…ri_env test

docs/cpp-interface.md

@@ -37,6 +37,18 @@ ale::Action a = legal_actions[rand() % legal_actions.size()];
 float reward = ale.act(a);
 ```
 
+An optional sound observation is provided. To enable, set the associated environment parameter:
+
+```cpp
+ale.setBool("sound_obs", True);
+```
+
+Once enabled, the sound observation may be obtained by calling:
+
+```cpp
+ale.getAudio()
+```
+
 Finally, one can check whether the episode has terminated using the function `ale.game_over()`. With these functions one can already implement a very simple agent that plays randomly for one episode:
 
 ```cpp

src/ale/common/SoundRaw.cxx

@@ -120,15 +120,15 @@ void SoundRaw::set(uint16_t addr, uint8_t value, int cycle)
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void SoundRaw::process(uint8_t* buffer, uint32_t samples)
 {
-  // Process all the audio register updates up to this frame 
+  // Process all the audio register updates up to this frame
   // Set audio registers
   uint32_t regSize = myRegWriteQueue.size();
   for(uint32_t i = 0; i < regSize; ++i) {
     TIARegister& info = myRegWriteQueue.front();
     myTIASound.set(info.addr, info.value);
     myRegWriteQueue.pop_front();
   }
-  
+
   // Process audio registers
   myTIASound.process(buffer, samples);
 }

src/ale/common/SoundRaw.hxx

@@ -194,7 +194,7 @@ private:
     // Indicates the cycle when a sound register was last set
     int myLastRegisterSetCycle;
 
-    // Queue of TIA register writes 
+    // Queue of TIA register writes
     std::deque<TIARegister> myRegWriteQueue;
 };
 

src/ale/python/env.py

@@ -74,7 +74,7 @@ def __init__(
               game sounds. This will lock emulation to the ROMs specified FPS
               If `rgb_array` we'll return the `rgb` key in step metadata with
               the current environment RGB frame.
-          sound_obs: bool => Add teh sound from the frame to the observation.
+          sound_obs: bool => Add the sound from the frame to the observation.
 
         Note:
           - The game must be installed, see ale-import-roms, or ale-py-roms.

tests/python/test_atari_env.py

@@ -399,3 +399,12 @@ def test_gym_compliance(tetris_env):
         check_env(tetris_env.unwrapped, skip_render_check=True)
 
     assert len(caught_warnings) == 0, [w.message for w in caught_warnings]
+
+
+def test_sound_obs():
+    env = gymnasium.make("ALE/MsPacman-v5", sound_obs=True)
+
+    with warnings.catch_warnings(record=True) as caught_warnings:
+        check_env(env.unwrapped, skip_render_check=True)
+
+    assert caught_warnings == [], [caught.message.args[0] for caught in caught_warnings]