diff --git a/fft-graph.py b/fft-graph.py
index 7e98ca1..5f08c09 100644
--- a/fft-graph.py
+++ b/fft-graph.py
@@ -32,34 +32,30 @@ freq = freq[left:right]
 values = values[left:right]
 
 # Génération du graphe
-plt.style.use('ggplot')
 plt.rcParams.update({
     'figure.figsize': (10, 5),
-    'font.size': 16,
+    'font.size': 18,
     'font.family': 'Concourse T4',
 })
 
 fig, ax = plt.subplots()
 ax.tick_params(axis='both', which='major', labelsize=12)
 ax.plot(freq, values)
+ax.grid(alpha=.3)
 
 # Configuration des axes
-def freq_format(value, pos):
-    return f'{value * freq_scale:.0f} Hz'
-
-
-def ampl_format(value, pos):
-    return f'{value:.1f}'
-
-
 ax.set_xlabel('Fréquence', labelpad=10)
 ax.set_xscale('log', base=2)
-ax.xaxis.set_major_formatter(matplotlib.ticker.FuncFormatter(freq_format))
-ax.xaxis.set_major_locator(plt.MultipleLocator(100 / freq_scale))
+ax.xaxis.set_major_formatter(matplotlib.ticker.FuncFormatter(lambda x, pos: f'{x * freq_scale:.0f} Hz'))
+ax.xaxis.set_major_locator(matplotlib.ticker.MultipleLocator(100 / freq_scale))
+ax.xaxis.set_minor_formatter(matplotlib.ticker.NullFormatter())
+ax.xaxis.set_minor_locator(matplotlib.ticker.MultipleLocator(10 / freq_scale))
 
 ax.set_ylabel('Amplitude relative', labelpad=10)
-ax.yaxis.set_major_formatter(matplotlib.ticker.FuncFormatter(ampl_format))
-ax.yaxis.set_major_locator(plt.MultipleLocator(.2))
+ax.yaxis.set_major_formatter(matplotlib.ticker.StrMethodFormatter('{x:.1f}'))
+ax.yaxis.set_major_locator(matplotlib.ticker.MultipleLocator(.2))
+ax.yaxis.set_minor_formatter(matplotlib.ticker.NullFormatter())
+ax.yaxis.set_minor_locator(matplotlib.ticker.MultipleLocator(.05))
 
 # Rendu du résultat
 if output_file == '-':
diff --git a/fig/piano-fft.png b/fig/piano-fft.png
index 01eb74a..73b7cdd 100644
Binary files a/fig/piano-fft.png and b/fig/piano-fft.png differ
diff --git a/fig/piano-stft.png b/fig/piano-stft.png
index d96d3d0..2676692 100644
Binary files a/fig/piano-stft.png and b/fig/piano-stft.png differ
diff --git a/fig/synth-fft.png b/fig/synth-fft.png
index b37c593..9e3857a 100644
Binary files a/fig/synth-fft.png and b/fig/synth-fft.png differ
diff --git a/fig/synth-stft.png b/fig/synth-stft.png
index 9dab7e6..0292dbe 100644
Binary files a/fig/synth-stft.png and b/fig/synth-stft.png differ
diff --git a/stft-graph.py b/stft-graph.py
index dc5f47f..ab0ba57 100644
--- a/stft-graph.py
+++ b/stft-graph.py
@@ -17,45 +17,47 @@ output_file = sys.argv[2]
 
 # Calcul du STFT
 signal = soundbox.load_signal(source_file)
+
 freq, time, vecs = sig.stft(signal, soundbox.samp_rate, nperseg=soundbox.samp_rate * 0.5)
 values = np.absolute(vecs)
 
+# Calcul de la fenêtre des fréquences intéressantes
+high_enough = np.where(values.max(axis=1) / np.max(values) >= 0.01)
+left = high_enough[0][0]
+right = high_enough[0][-1]
+
+freq = freq[left:right]
+values = values[left:right]
+
 # Génération du graphe
 plt.rcParams.update({
     'figure.figsize': (10, 8),
-    'figure.frameon': True,
-    'font.size': 20,
+    'font.size': 18,
     'font.family': 'Concourse T4',
 })
 
-fig, ax = plt.subplots(frameon=True)
+fig, ax = plt.subplots()
 ax.tick_params(axis='both', which='major', labelsize=12)
-
-freq_filter = values.max(axis=1) / np.max(values) >= 0.01
-x = np.arange(len(values))
-
-ax.pcolormesh(
-    time, freq[freq_filter], values[freq_filter],
-    cmap='Greys',
-    shading='gouraud')
+ax.pcolormesh(time, freq, values, cmap='Greys', shading='gouraud')
+ax.grid(alpha=.3)
 
 # Configuration des axes
-def time_format(value, pos):
-    return f'{value:.0f} s'
-
-
 def freq_format(value, pos):
     return f'{value:.0f} Hz'
 
 
 ax.set_xlabel('Temps', labelpad=10)
-ax.xaxis.set_major_formatter(matplotlib.ticker.FuncFormatter(time_format))
+ax.xaxis.set_major_formatter(matplotlib.ticker.StrMethodFormatter('{x:.0f} s'))
+ax.xaxis.set_major_locator(matplotlib.ticker.MultipleLocator(1))
+ax.xaxis.set_minor_formatter(matplotlib.ticker.NullFormatter())
+ax.xaxis.set_minor_locator(matplotlib.ticker.MultipleLocator(.2))
 
 ax.set_ylabel('Fréquence', labelpad=10)
 ax.set_yscale('log', base=2)
 ax.yaxis.set_major_locator(plt.MultipleLocator(100))
-ax.yaxis.set_major_formatter(matplotlib.ticker.FuncFormatter(freq_format))
-ax.grid(alpha=.3)
+ax.yaxis.set_major_formatter(matplotlib.ticker.StrMethodFormatter('{x:.0f} Hz'))
+ax.yaxis.set_minor_formatter(matplotlib.ticker.NullFormatter())
+ax.yaxis.set_minor_locator(matplotlib.ticker.MultipleLocator(10))
 
 # Rendu du résultat
 if output_file == '-':