From 07a8993e8ca0049842cd90f90a3c436618e82e7e Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 17:26:48 +0900
Subject: [PATCH 01/15] Fix indentation of code sample in document comment

---
 bindings/ruby/sig/whisper.rbs | 68 +++++++++++++++++------------------
 1 file changed, 34 insertions(+), 34 deletions(-)

diff --git a/bindings/ruby/sig/whisper.rbs b/bindings/ruby/sig/whisper.rbs
index 6f8be29a66b..2cffc6fecf4 100644
--- a/bindings/ruby/sig/whisper.rbs
+++ b/bindings/ruby/sig/whisper.rbs
@@ -30,11 +30,11 @@ module Whisper
     # transcribe a single file
     # can emit to a block results
     #
-    #   params = Whisper::Params.new
-    #   params.duration = 60_000
-    #   whisper.transcribe "path/to/audio.wav", params do |text|
-    #     puts text
-    #   end
+    #     params = Whisper::Params.new
+    #     params.duration = 60_000
+    #     whisper.transcribe "path/to/audio.wav", params do |text|
+    #       puts text
+    #     end
     #
     def transcribe: (string, Params) -> self
                   | (string, Params) { (String) -> void } -> self
@@ -50,16 +50,16 @@ module Whisper
 
     # Yields each Whisper::Segment:
     #
-    #   whisper.transcribe("path/to/audio.wav", params)
-    #   whisper.each_segment do |segment|
-    #     puts segment.text
-    #   end
+    #     whisper.transcribe("path/to/audio.wav", params)
+    #     whisper.each_segment do |segment|
+    #       puts segment.text
+    #     end
     #
     # Returns an Enumerator if no block given:
     #
-    #   whisper.transcribe("path/to/audio.wav", params)
-    #   enum = whisper.each_segment
-    #   enum.to_a # => [#<Whisper::Segment>, ...]
+    #     whisper.transcribe("path/to/audio.wav", params)
+    #     enum = whisper.each_segment
+    #     enum.to_a # => [#<Whisper::Segment>, ...]
     #
     def each_segment: { (Segment) -> void } -> void
                     | () -> Enumerator[Segment]
@@ -74,25 +74,25 @@ module Whisper
 
     # Start time of a segment indexed by +segment_index+ in centiseconds (10 times milliseconds).
     #
-    #   full_get_segment_t0(3) # => 1668 (16680 ms)
+    #     full_get_segment_t0(3) # => 1668 (16680 ms)
     #
     def full_get_segment_t0: (Integer) -> Integer
 
     # End time of a segment indexed by +segment_index+ in centiseconds (10 times milliseconds).
     #
-    #   full_get_segment_t1(3) # => 1668 (16680 ms)
+    #     full_get_segment_t1(3) # => 1668 (16680 ms)
     #
     def full_get_segment_t1: (Integer) -> Integer
 
     # Whether the next segment indexed by +segment_index+ is predicated as a speaker turn.
     #
-    #   full_get_segment_speacker_turn_next(3) # => true
+    #     full_get_segment_speacker_turn_next(3) # => true
     #
     def full_get_segment_speaker_turn_next: (Integer) -> (true | false)
 
     # Text of a segment indexed by +segment_index+.
     #
-    #   full_get_segment_text(3) # => "ask not what your country can do for you, ..."
+    #     full_get_segment_text(3) # => "ask not what your country can do for you, ..."
     #
     def full_get_segment_text: (Integer) -> String
 
@@ -282,9 +282,9 @@ module Whisper
 
     # Sets new segment callback, called for every newly generated text segment.
     #
-    #   params.new_segment_callback = ->(context, _, n_new, user_data) {
-    #     # ...
-    #   }
+    #     params.new_segment_callback = ->(context, _, n_new, user_data) {
+    #       # ...
+    #     }
     #
     def new_segment_callback=: (new_segment_callback) -> new_segment_callback
     def new_segment_callback: () -> (new_segment_callback | nil)
@@ -297,9 +297,9 @@ module Whisper
 
     # Sets progress callback, called on each progress update.
     #
-    #   params.new_segment_callback = ->(context, _, progress, user_data) {
-    #     # ...
-    #   }
+    #     params.new_segment_callback = ->(context, _, progress, user_data) {
+    #       # ...
+    #     }
     #
     # +progress+ is an Integer between 0 and 100.
     #
@@ -327,9 +327,9 @@ module Whisper
 
     # Sets abort callback, called to check if the process should be aborted.
     #
-    #   params.abort_callback = ->(user_data) {
-    #     # ...
-    #   }
+    #     params.abort_callback = ->(user_data) {
+    #       # ...
+    #     }
     #
     #
     def abort_callback=: (abort_callback) -> abort_callback
@@ -358,9 +358,9 @@ module Whisper
 
     # Hook called on new segment. Yields each Whisper::Segment.
     #
-    #   whisper.on_new_segment do |segment|
-    #     # ...
-    #   end
+    #     whisper.on_new_segment do |segment|
+    #       # ...
+    #     end
     #
     def on_new_segment: { (Segment) -> void } -> void
 
@@ -374,13 +374,13 @@ module Whisper
 
     # Call block to determine whether abort or not. Return +true+ when you want to abort.
     #
-    #   params.abort_on do
-    #     if some_condition
-    #       true # abort
-    #     else
-    #       false # continue
+    #     params.abort_on do
+    #       if some_condition
+    #         true # abort
+    #       else
+    #         false # continue
+    #       end
     #     end
-    #   end
     #
     def abort_on: { (Object user_data) -> boolish } -> void
   end

From 7cf7ac3f9b202f49b63f0fbf65986e7deea5c5d3 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 19:33:31 +0900
Subject: [PATCH 02/15] Make Whisper::Context#transcribe able to run
 non-parallel

---
 bindings/ruby/ext/ruby_whisper.c              |  2 ++
 bindings/ruby/ext/ruby_whisper_context.c      |  5 +++++
 bindings/ruby/ext/ruby_whisper_transcribe.cpp | 19 +++++++++++++++----
 3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/bindings/ruby/ext/ruby_whisper.c b/bindings/ruby/ext/ruby_whisper.c
index e88aa29c05d..3fc36027135 100644
--- a/bindings/ruby/ext/ruby_whisper.c
+++ b/bindings/ruby/ext/ruby_whisper.c
@@ -24,6 +24,7 @@ ID id_URI;
 ID id_pre_converted_models;
 ID id_coreml_compiled_models;
 ID id_cache;
+ID id_parallel;
 
 static bool is_log_callback_finalized = false;
 
@@ -142,6 +143,7 @@ void Init_whisper() {
   id_pre_converted_models = rb_intern("pre_converted_models");
   id_coreml_compiled_models = rb_intern("coreml_compiled_models");
   id_cache = rb_intern("cache");
+  id_parallel = rb_intern("parallel");
 
   mWhisper = rb_define_module("Whisper");
   mVAD = rb_define_module_under(mWhisper, "VAD");
diff --git a/bindings/ruby/ext/ruby_whisper_context.c b/bindings/ruby/ext/ruby_whisper_context.c
index 75aa8dc9065..0e16c1adece 100644
--- a/bindings/ruby/ext/ruby_whisper_context.c
+++ b/bindings/ruby/ext/ruby_whisper_context.c
@@ -13,6 +13,7 @@ extern ID id_URI;
 extern ID id_pre_converted_models;
 extern ID id_coreml_compiled_models;
 extern ID id_cache;
+extern ID id_parallel;
 
 extern VALUE cContext;
 extern VALUE eError;
@@ -24,6 +25,8 @@ extern VALUE rb_whisper_model_s_new(VALUE context);
 extern VALUE rb_whisper_segment_s_new(VALUE context, int index);
 extern void prepare_transcription(ruby_whisper_params *rwp, VALUE *context);
 
+ID transcribe_option_names[1];
+
 static void
 ruby_whisper_free(ruby_whisper *rw)
 {
@@ -633,6 +636,8 @@ init_ruby_whisper_context(VALUE *mWhisper)
 {
   cContext = rb_define_class_under(*mWhisper, "Context", rb_cObject);
 
+  transcribe_option_names[0] = id_parallel;
+
   rb_define_alloc_func(cContext, ruby_whisper_allocate);
   rb_define_method(cContext, "initialize", ruby_whisper_initialize, -1);
 
diff --git a/bindings/ruby/ext/ruby_whisper_transcribe.cpp b/bindings/ruby/ext/ruby_whisper_transcribe.cpp
index d12d2de96fe..a921a9b5a2b 100644
--- a/bindings/ruby/ext/ruby_whisper_transcribe.cpp
+++ b/bindings/ruby/ext/ruby_whisper_transcribe.cpp
@@ -13,6 +13,7 @@ extern const rb_data_type_t ruby_whisper_params_type;
 
 extern ID id_to_s;
 extern ID id_call;
+extern ID transcribe_option_names[1];
 
 extern void
 prepare_transcription(ruby_whisper_params * rwp, VALUE * self);
@@ -34,9 +35,14 @@ VALUE
 ruby_whisper_transcribe(int argc, VALUE *argv, VALUE self) {
   ruby_whisper *rw;
   ruby_whisper_params *rwp;
-  VALUE wave_file_path, blk, params;
+  VALUE wave_file_path, blk, params, kws;
+  VALUE opts[1];
+
+  rb_scan_args_kw(RB_SCAN_ARGS_LAST_HASH_KEYWORDS, argc, argv, "2:&", &wave_file_path, &params, &kws, &blk);
+  rb_get_kwargs(kws, transcribe_option_names, 0, 1, opts);
+
+  bool parallel = !(NIL_P(opts[0]) || opts[0] == Qfalse);
 
-  rb_scan_args(argc, argv, "02&", &wave_file_path, &params, &blk);
   TypedData_Get_Struct(self, ruby_whisper, &ruby_whisper_type, rw);
   TypedData_Get_Struct(params, ruby_whisper_params, &ruby_whisper_params_type, rwp);
 
@@ -66,8 +72,13 @@ ruby_whisper_transcribe(int argc, VALUE *argv, VALUE self) {
 
   prepare_transcription(rwp, &self);
 
-  if (whisper_full_parallel(rw->context, rwp->params, pcmf32.data(), pcmf32.size(), 1) != 0) {
-    fprintf(stderr, "failed to process audio\n");
+  int result;
+  if (parallel) {
+    result = whisper_full_parallel(rw->context, rwp->params, pcmf32.data(), pcmf32.size(), 1);
+  } else {
+    result = whisper_full(rw->context, rwp->params, pcmf32.data(), pcmf32.size());
+  }
+  if (result != 0) {
     return self;
   }
   const int n_segments = whisper_full_n_segments(rw->context);

From ba9155eb27f78dd57e18338ae7c54f5f6b411dc2 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 19:33:47 +0900
Subject: [PATCH 03/15] Add test for Whisper::Context#transcribe with parallel
 option

---
 bindings/ruby/tests/test_whisper.rb | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/bindings/ruby/tests/test_whisper.rb b/bindings/ruby/tests/test_whisper.rb
index d915041f366..e0bf353e966 100644
--- a/bindings/ruby/tests/test_whisper.rb
+++ b/bindings/ruby/tests/test_whisper.rb
@@ -20,6 +20,15 @@ def test_whisper
     }
   end
 
+  def test_transcribe_non_parallel
+    @whisper = Whisper::Context.new("base.en")
+    params  = Whisper::Params.new
+
+    @whisper.transcribe(AUDIO, params, parallel: false) {|text|
+      assert_match(/ask not what your country can do for you, ask what you can do for your country/, text)
+    }
+  end
+
   sub_test_case "After transcription" do
     def test_full_n_segments
       assert_equal 1, whisper.full_n_segments

From c357a81ce3359467d8c7a6a98b904ac414110573 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 19:36:29 +0900
Subject: [PATCH 04/15] Follow signature API change of Context#transcribe

---
 bindings/ruby/sig/whisper.rbs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/bindings/ruby/sig/whisper.rbs b/bindings/ruby/sig/whisper.rbs
index 2cffc6fecf4..bddaa4411cc 100644
--- a/bindings/ruby/sig/whisper.rbs
+++ b/bindings/ruby/sig/whisper.rbs
@@ -36,8 +36,8 @@ module Whisper
     #       puts text
     #     end
     #
-    def transcribe: (string, Params) -> self
-                  | (string, Params) { (String) -> void } -> self
+    def transcribe: (string, Params, ?parallel: boolish) -> self
+                  | (string, Params, ?parallel: boolish) { (String) -> void } -> self
 
     def model_n_vocab: () -> Integer
     def model_n_audio_ctx: () -> Integer

From 5222a6695993a77f5e899fdb8ba4802f200f660d Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 19:36:52 +0900
Subject: [PATCH 05/15] Remove useless variable assignment

---
 bindings/ruby/ext/ruby_whisper_transcribe.cpp | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/bindings/ruby/ext/ruby_whisper_transcribe.cpp b/bindings/ruby/ext/ruby_whisper_transcribe.cpp
index a921a9b5a2b..bd4739cb0b6 100644
--- a/bindings/ruby/ext/ruby_whisper_transcribe.cpp
+++ b/bindings/ruby/ext/ruby_whisper_transcribe.cpp
@@ -87,9 +87,8 @@ ruby_whisper_transcribe(int argc, VALUE *argv, VALUE self) {
     const char * text = whisper_full_get_segment_text(rw->context, i);
     output = rb_str_concat(output, rb_str_new2(text));
   }
-  VALUE idCall = id_call;
   if (blk != Qnil) {
-    rb_funcall(blk, idCall, 1, output);
+    rb_funcall(blk, id_call, 1, output);
   }
   return self;
 }

From 7a4ac91a0bd1c0b343aec243dc2575fcbc5ac71c Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 19:44:02 +0900
Subject: [PATCH 06/15] Move simple usage up in README

---
 bindings/ruby/README.md | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/bindings/ruby/README.md b/bindings/ruby/README.md
index 6de00fb275b..112ea989d23 100644
--- a/bindings/ruby/README.md
+++ b/bindings/ruby/README.md
@@ -70,17 +70,6 @@ end
 
 Some models are prepared up-front:
 
-```ruby
-base_en = Whisper::Model.pre_converted_models["base.en"]
-whisper = Whisper::Context.new(base_en)
-```
-
-At first time you use a model, it is downloaded automatically. After that, downloaded cached file is used. To clear cache, call `#clear_cache`:
-
-```ruby
-Whisper::Model.pre_converted_models["base"].clear_cache
-```
-
 You also can use shorthand for pre-converted models:
 
 ```ruby
@@ -105,6 +94,19 @@ puts Whisper::Model.pre_converted_models.keys
 #   :
 ```
 
+You can also retrieve each model:
+
+```ruby
+base_en = Whisper::Model.pre_converted_models["base.en"]
+whisper = Whisper::Context.new(base_en)
+```
+
+At first time you use a model, it is downloaded automatically. After that, downloaded cached file is used. To clear cache, call `#clear_cache`:
+
+```ruby
+Whisper::Model.pre_converted_models["base"].clear_cache
+```
+
 You can also use local model files you prepared:
 
 ```ruby

From b8f966b13d0e7cb39d6f9c20ffe032fdf69ef097 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 19:45:01 +0900
Subject: [PATCH 07/15] Add need help section in README

---
 bindings/ruby/README.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/bindings/ruby/README.md b/bindings/ruby/README.md
index 112ea989d23..9cf05717ee3 100644
--- a/bindings/ruby/README.md
+++ b/bindings/ruby/README.md
@@ -299,6 +299,11 @@ First call of `rake test` builds an extension and downloads a model for testing.
 
 If something seems wrong on build, running `rake clean` solves some cases.
 
+### Need help ###
+
+* Windows support
+* Refinement of C/C++ code, especially memory management
+
 License
 -------
 

From 628f35e46a22b634342ab719353f80dfef3541b3 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 20:01:42 +0900
Subject: [PATCH 08/15] Add document on Context#transcribe's parallel option in
 README

---
 bindings/ruby/README.md | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/bindings/ruby/README.md b/bindings/ruby/README.md
index 9cf05717ee3..c97280e40c5 100644
--- a/bindings/ruby/README.md
+++ b/bindings/ruby/README.md
@@ -165,6 +165,16 @@ For details on VAD, see [whisper.cpp's README](https://github.com/ggml-org/whisp
 API
 ---
 
+### Transcription ###
+
+By default, `Whisper::Context#transcribe` works in parallel. You can make it work in single thread by passing `parallel: false`:
+
+```ruby
+whisper.transcribe("path/to/audio.wav", params, parallel: false)
+```
+
+Occasionally, transcription might be low accuracy when it works in parallel. Use `parallel: false` in such a case.
+
 ### Segments ###
 
 Once `Whisper::Context#transcribe` called, you can retrieve segments by `#each_segment`:

From f42317fbc081e534a53361f9db7effa6aa5c4f47 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 20:01:46 +0900
Subject: [PATCH 09/15] Update date

---
 bindings/ruby/whispercpp.gemspec | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bindings/ruby/whispercpp.gemspec b/bindings/ruby/whispercpp.gemspec
index 06bef943510..7c9aa4545a9 100644
--- a/bindings/ruby/whispercpp.gemspec
+++ b/bindings/ruby/whispercpp.gemspec
@@ -4,7 +4,7 @@ Gem::Specification.new do |s|
   s.name    = "whispercpp"
   s.authors = ["Georgi Gerganov", "Todd A. Fisher"]
   s.version = '1.3.3'
-  s.date    = '2025-06-01'
+  s.date    = '2025-06-03'
   s.description = %q{High-performance inference of OpenAI's Whisper automatic speech recognition (ASR) model via Ruby}
   s.email   = 'todd.fisher@gmail.com'
   s.extra_rdoc_files = ['LICENSE', 'README.md']

From 59aa9d0ea21d28746c05d30d21a89b6a22f54cf5 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 20:16:59 +0900
Subject: [PATCH 10/15] Fix signature of Context.new

---
 bindings/ruby/sig/whisper.rbs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bindings/ruby/sig/whisper.rbs b/bindings/ruby/sig/whisper.rbs
index bddaa4411cc..b5ea467daaf 100644
--- a/bindings/ruby/sig/whisper.rbs
+++ b/bindings/ruby/sig/whisper.rbs
@@ -25,7 +25,7 @@ module Whisper
   def self.system_info_str: () -> String
 
   class Context
-    def self.new: (path | ::URI::HTTP) -> instance
+    def self.new: (String | path | ::URI::HTTP) -> instance
 
     # transcribe a single file
     # can emit to a block results

From 81836a5fdf17bc5118f7580042ecdbfcf7515f57 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 23:38:00 +0900
Subject: [PATCH 11/15] Make Context#subscribe accept n_processors option

---
 bindings/ruby/ext/ruby_whisper.c              |  4 ++--
 bindings/ruby/ext/ruby_whisper_context.c      |  4 ++--
 bindings/ruby/ext/ruby_whisper_transcribe.cpp | 11 +++--------
 3 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/bindings/ruby/ext/ruby_whisper.c b/bindings/ruby/ext/ruby_whisper.c
index 3fc36027135..a1c2c520512 100644
--- a/bindings/ruby/ext/ruby_whisper.c
+++ b/bindings/ruby/ext/ruby_whisper.c
@@ -24,7 +24,7 @@ ID id_URI;
 ID id_pre_converted_models;
 ID id_coreml_compiled_models;
 ID id_cache;
-ID id_parallel;
+ID id_n_processors;
 
 static bool is_log_callback_finalized = false;
 
@@ -143,7 +143,7 @@ void Init_whisper() {
   id_pre_converted_models = rb_intern("pre_converted_models");
   id_coreml_compiled_models = rb_intern("coreml_compiled_models");
   id_cache = rb_intern("cache");
-  id_parallel = rb_intern("parallel");
+  id_n_processors = rb_intern("n_processors");
 
   mWhisper = rb_define_module("Whisper");
   mVAD = rb_define_module_under(mWhisper, "VAD");
diff --git a/bindings/ruby/ext/ruby_whisper_context.c b/bindings/ruby/ext/ruby_whisper_context.c
index 0e16c1adece..cb58c8d4877 100644
--- a/bindings/ruby/ext/ruby_whisper_context.c
+++ b/bindings/ruby/ext/ruby_whisper_context.c
@@ -13,7 +13,7 @@ extern ID id_URI;
 extern ID id_pre_converted_models;
 extern ID id_coreml_compiled_models;
 extern ID id_cache;
-extern ID id_parallel;
+extern ID id_n_processors;
 
 extern VALUE cContext;
 extern VALUE eError;
@@ -636,7 +636,7 @@ init_ruby_whisper_context(VALUE *mWhisper)
 {
   cContext = rb_define_class_under(*mWhisper, "Context", rb_cObject);
 
-  transcribe_option_names[0] = id_parallel;
+  transcribe_option_names[0] = id_n_processors;
 
   rb_define_alloc_func(cContext, ruby_whisper_allocate);
   rb_define_method(cContext, "initialize", ruby_whisper_initialize, -1);
diff --git a/bindings/ruby/ext/ruby_whisper_transcribe.cpp b/bindings/ruby/ext/ruby_whisper_transcribe.cpp
index bd4739cb0b6..71c4b49b45a 100644
--- a/bindings/ruby/ext/ruby_whisper_transcribe.cpp
+++ b/bindings/ruby/ext/ruby_whisper_transcribe.cpp
@@ -41,7 +41,7 @@ ruby_whisper_transcribe(int argc, VALUE *argv, VALUE self) {
   rb_scan_args_kw(RB_SCAN_ARGS_LAST_HASH_KEYWORDS, argc, argv, "2:&", &wave_file_path, &params, &kws, &blk);
   rb_get_kwargs(kws, transcribe_option_names, 0, 1, opts);
 
-  bool parallel = !(NIL_P(opts[0]) || opts[0] == Qfalse);
+  int n_processors = opts[0] == Qundef ? 1 : NUM2INT(opts[0]);
 
   TypedData_Get_Struct(self, ruby_whisper, &ruby_whisper_type, rw);
   TypedData_Get_Struct(params, ruby_whisper_params, &ruby_whisper_params_type, rwp);
@@ -72,13 +72,8 @@ ruby_whisper_transcribe(int argc, VALUE *argv, VALUE self) {
 
   prepare_transcription(rwp, &self);
 
-  int result;
-  if (parallel) {
-    result = whisper_full_parallel(rw->context, rwp->params, pcmf32.data(), pcmf32.size(), 1);
-  } else {
-    result = whisper_full(rw->context, rwp->params, pcmf32.data(), pcmf32.size());
-  }
-  if (result != 0) {
+  if (whisper_full_parallel(rw->context, rwp->params, pcmf32.data(), pcmf32.size(), n_processors) != 0) {
+    fprintf(stderr, "failed to process audio\n");
     return self;
   }
   const int n_segments = whisper_full_n_segments(rw->context);

From f95c060e4ee7951d5e6419651c9b894b92d2aeac Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 23:38:29 +0900
Subject: [PATCH 12/15] Make test follow #transcribe's change

---
 bindings/ruby/tests/test_whisper.rb | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/bindings/ruby/tests/test_whisper.rb b/bindings/ruby/tests/test_whisper.rb
index e0bf353e966..8f1e69db86b 100644
--- a/bindings/ruby/tests/test_whisper.rb
+++ b/bindings/ruby/tests/test_whisper.rb
@@ -24,11 +24,20 @@ def test_transcribe_non_parallel
     @whisper = Whisper::Context.new("base.en")
     params  = Whisper::Params.new
 
-    @whisper.transcribe(AUDIO, params, parallel: false) {|text|
+    @whisper.transcribe(AUDIO, params, n_processors: 1) {|text|
       assert_match(/ask not what your country can do for you, ask what you can do for your country/, text)
     }
   end
 
+  def test_transcribe_n_processors
+    @whisper = Whisper::Context.new("base.en")
+    params  = Whisper::Params.new
+
+    @whisper.transcribe(AUDIO, params, n_processors: 4) {|text|
+      assert_match(/ask not what your country can do for you[,.] ask what you can do for your country/i, text)
+    }
+  end
+
   sub_test_case "After transcription" do
     def test_full_n_segments
       assert_equal 1, whisper.full_n_segments

From 19b2757da95e37e7c506b4ca785855285cc92999 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 23:39:09 +0900
Subject: [PATCH 13/15] Make RBS follow #transcribe's change

---
 bindings/ruby/sig/whisper.rbs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/bindings/ruby/sig/whisper.rbs b/bindings/ruby/sig/whisper.rbs
index b5ea467daaf..f9d09631509 100644
--- a/bindings/ruby/sig/whisper.rbs
+++ b/bindings/ruby/sig/whisper.rbs
@@ -36,8 +36,8 @@ module Whisper
     #       puts text
     #     end
     #
-    def transcribe: (string, Params, ?parallel: boolish) -> self
-                  | (string, Params, ?parallel: boolish) { (String) -> void } -> self
+    def transcribe: (string, Params, ?n_processors: Integer) -> self
+                  | (string, Params, ?n_processors: Integer) { (String) -> void } -> self
 
     def model_n_vocab: () -> Integer
     def model_n_audio_ctx: () -> Integer

From a7de86c8cf0549f4f6ae0887928c5ad3b828d6a1 Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 23:51:53 +0900
Subject: [PATCH 14/15] Add document for #transcribe's n_processors option

---
 bindings/ruby/README.md | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/bindings/ruby/README.md b/bindings/ruby/README.md
index c97280e40c5..5ba88e6f8d5 100644
--- a/bindings/ruby/README.md
+++ b/bindings/ruby/README.md
@@ -167,13 +167,13 @@ API
 
 ### Transcription ###
 
-By default, `Whisper::Context#transcribe` works in parallel. You can make it work in single thread by passing `parallel: false`:
+By default, `Whisper::Context#transcribe` works in a single thread. You can make it work in parallel by passing `n_processors` option:
 
 ```ruby
-whisper.transcribe("path/to/audio.wav", params, parallel: false)
+whisper.transcribe("path/to/audio.wav", params, n_processors: Etc.nprocessors)
 ```
 
-Occasionally, transcription might be low accuracy when it works in parallel. Use `parallel: false` in such a case.
+Note that transcription occasionally might be low accuracy when it works in parallel.
 
 ### Segments ###
 

From 9f2763421bb849e9e0a461694543daad6251e15a Mon Sep 17 00:00:00 2001
From: Kitaiti Makoto <KitaitiMakoto@gmail.com>
Date: Tue, 3 Jun 2025 23:58:22 +0900
Subject: [PATCH 15/15] Rename test directory so that Rake tasks' default
 setting is used

---
 bindings/ruby/Rakefile                               | 12 +++++-------
 bindings/ruby/{tests => test}/helper.rb              |  0
 bindings/ruby/{tests => test}/jfk_reader/.gitignore  |  0
 bindings/ruby/{tests => test}/jfk_reader/extconf.rb  |  0
 .../ruby/{tests => test}/jfk_reader/jfk_reader.c     |  0
 bindings/ruby/{tests => test}/test_callback.rb       |  0
 bindings/ruby/{tests => test}/test_error.rb          |  0
 bindings/ruby/{tests => test}/test_model.rb          |  0
 bindings/ruby/{tests => test}/test_package.rb        |  0
 bindings/ruby/{tests => test}/test_params.rb         |  0
 bindings/ruby/{tests => test}/test_segment.rb        |  0
 bindings/ruby/{tests => test}/test_vad.rb            |  0
 bindings/ruby/{tests => test}/test_vad_params.rb     |  0
 bindings/ruby/{tests => test}/test_whisper.rb        |  0
 bindings/ruby/whispercpp.gemspec                     |  2 +-
 15 files changed, 6 insertions(+), 8 deletions(-)
 rename bindings/ruby/{tests => test}/helper.rb (100%)
 rename bindings/ruby/{tests => test}/jfk_reader/.gitignore (100%)
 rename bindings/ruby/{tests => test}/jfk_reader/extconf.rb (100%)
 rename bindings/ruby/{tests => test}/jfk_reader/jfk_reader.c (100%)
 rename bindings/ruby/{tests => test}/test_callback.rb (100%)
 rename bindings/ruby/{tests => test}/test_error.rb (100%)
 rename bindings/ruby/{tests => test}/test_model.rb (100%)
 rename bindings/ruby/{tests => test}/test_package.rb (100%)
 rename bindings/ruby/{tests => test}/test_params.rb (100%)
 rename bindings/ruby/{tests => test}/test_segment.rb (100%)
 rename bindings/ruby/{tests => test}/test_vad.rb (100%)
 rename bindings/ruby/{tests => test}/test_vad_params.rb (100%)
 rename bindings/ruby/{tests => test}/test_whisper.rb (100%)

diff --git a/bindings/ruby/Rakefile b/bindings/ruby/Rakefile
index bc6f843369b..08a2312a551 100644
--- a/bindings/ruby/Rakefile
+++ b/bindings/ruby/Rakefile
@@ -67,17 +67,15 @@ file LIB_FILE => [SO_FILE, "lib"] do |t|
 end
 CLEAN.include LIB_FILE
 
-Rake::TestTask.new do |t|
-  t.test_files = FileList["tests/test_*.rb"]
-end
+Rake::TestTask.new
 
-TEST_MEMORY_VIEW = "tests/jfk_reader/jfk_reader.#{RbConfig::CONFIG['DLEXT']}"
-file TEST_MEMORY_VIEW => "tests/jfk_reader/jfk_reader.c" do |t|
-  chdir "tests/jfk_reader" do
+TEST_MEMORY_VIEW = "test/jfk_reader/jfk_reader.#{RbConfig::CONFIG['DLEXT']}"
+file TEST_MEMORY_VIEW => "test/jfk_reader/jfk_reader.c" do |t|
+  chdir "test/jfk_reader" do
     ruby "extconf.rb"
     sh "make"
   end
 end
-CLEAN.include "tests/jfk_reader/jfk_reader.{o,#{RbConfig::CONFIG['DLEXT']}}"
+CLEAN.include "test/jfk_reader/jfk_reader.{o,#{RbConfig::CONFIG['DLEXT']}}"
 
 task test: [LIB_FILE, TEST_MEMORY_VIEW]
diff --git a/bindings/ruby/tests/helper.rb b/bindings/ruby/test/helper.rb
similarity index 100%
rename from bindings/ruby/tests/helper.rb
rename to bindings/ruby/test/helper.rb
diff --git a/bindings/ruby/tests/jfk_reader/.gitignore b/bindings/ruby/test/jfk_reader/.gitignore
similarity index 100%
rename from bindings/ruby/tests/jfk_reader/.gitignore
rename to bindings/ruby/test/jfk_reader/.gitignore
diff --git a/bindings/ruby/tests/jfk_reader/extconf.rb b/bindings/ruby/test/jfk_reader/extconf.rb
similarity index 100%
rename from bindings/ruby/tests/jfk_reader/extconf.rb
rename to bindings/ruby/test/jfk_reader/extconf.rb
diff --git a/bindings/ruby/tests/jfk_reader/jfk_reader.c b/bindings/ruby/test/jfk_reader/jfk_reader.c
similarity index 100%
rename from bindings/ruby/tests/jfk_reader/jfk_reader.c
rename to bindings/ruby/test/jfk_reader/jfk_reader.c
diff --git a/bindings/ruby/tests/test_callback.rb b/bindings/ruby/test/test_callback.rb
similarity index 100%
rename from bindings/ruby/tests/test_callback.rb
rename to bindings/ruby/test/test_callback.rb
diff --git a/bindings/ruby/tests/test_error.rb b/bindings/ruby/test/test_error.rb
similarity index 100%
rename from bindings/ruby/tests/test_error.rb
rename to bindings/ruby/test/test_error.rb
diff --git a/bindings/ruby/tests/test_model.rb b/bindings/ruby/test/test_model.rb
similarity index 100%
rename from bindings/ruby/tests/test_model.rb
rename to bindings/ruby/test/test_model.rb
diff --git a/bindings/ruby/tests/test_package.rb b/bindings/ruby/test/test_package.rb
similarity index 100%
rename from bindings/ruby/tests/test_package.rb
rename to bindings/ruby/test/test_package.rb
diff --git a/bindings/ruby/tests/test_params.rb b/bindings/ruby/test/test_params.rb
similarity index 100%
rename from bindings/ruby/tests/test_params.rb
rename to bindings/ruby/test/test_params.rb
diff --git a/bindings/ruby/tests/test_segment.rb b/bindings/ruby/test/test_segment.rb
similarity index 100%
rename from bindings/ruby/tests/test_segment.rb
rename to bindings/ruby/test/test_segment.rb
diff --git a/bindings/ruby/tests/test_vad.rb b/bindings/ruby/test/test_vad.rb
similarity index 100%
rename from bindings/ruby/tests/test_vad.rb
rename to bindings/ruby/test/test_vad.rb
diff --git a/bindings/ruby/tests/test_vad_params.rb b/bindings/ruby/test/test_vad_params.rb
similarity index 100%
rename from bindings/ruby/tests/test_vad_params.rb
rename to bindings/ruby/test/test_vad_params.rb
diff --git a/bindings/ruby/tests/test_whisper.rb b/bindings/ruby/test/test_whisper.rb
similarity index 100%
rename from bindings/ruby/tests/test_whisper.rb
rename to bindings/ruby/test/test_whisper.rb
diff --git a/bindings/ruby/whispercpp.gemspec b/bindings/ruby/whispercpp.gemspec
index 7c9aa4545a9..b838aa9fbde 100644
--- a/bindings/ruby/whispercpp.gemspec
+++ b/bindings/ruby/whispercpp.gemspec
@@ -21,7 +21,7 @@ Gem::Specification.new do |s|
               }
 
   s.summary = %q{Ruby whisper.cpp bindings}
-  s.test_files = s.files.select {|file| file.start_with? "tests/"}
+  s.test_files = s.files.select {|file| file.start_with? "test/"}
 
   s.extensions << 'ext/extconf.rb'
   s.required_ruby_version = '>= 3.1.0'