diff --git a/libvmaf/src/output.c b/libvmaf/src/output.c
index 039657ff7..70e09203a 100644
--- a/libvmaf/src/output.c
+++ b/libvmaf/src/output.c
@@ -19,6 +19,7 @@
 #include <errno.h>
 #include <math.h>
 #include <stdio.h>
+#include <locale.h>
 
 #include "feature/alias.h"
 #include "feature/feature_collector.h"
@@ -72,6 +73,12 @@ int vmaf_write_output_xml(VmafContext *vmaf, VmafFeatureCollector *fc,
     if (!fc) return -EINVAL;
     if (!outfile) return -EINVAL;
 
+    locale_t c_locale = newlocale(LC_ALL_MASK, "C", NULL);
+    locale_t old_locale = (locale_t)0;
+    if (c_locale != (locale_t)0) {
+        old_locale = uselocale(c_locale);
+    }
+
     fprintf(outfile, "<VMAF version=\"%s\">\n", vmaf_version());
     fprintf(outfile, "  <params qualityWidth=\"%d\" qualityHeight=\"%d\" />\n",
             width, height);
@@ -154,6 +161,11 @@ int vmaf_write_output_xml(VmafContext *vmaf, VmafFeatureCollector *fc,
 
     fprintf(outfile, "</VMAF>\n");
 
+    if (c_locale != (locale_t)0) {
+        uselocale(old_locale);
+        freelocale(c_locale);
+    }
+
     return 0;
 }
 
@@ -161,6 +173,12 @@ int vmaf_write_output_json(VmafContext *vmaf, VmafFeatureCollector *fc,
                            FILE *outfile, unsigned subsample, double fps,
                            unsigned pic_cnt)
 {
+    locale_t c_locale = newlocale(LC_ALL_MASK, "C", NULL);
+    locale_t old_locale = (locale_t)0;
+    if (c_locale != (locale_t)0) {
+        old_locale = uselocale(c_locale);
+    }
+
     int leading_zeros_count;
     fprintf(outfile, "{\n");
     fprintf(outfile, "  \"version\": \"%s\",\n", vmaf_version());
@@ -299,12 +317,23 @@ int vmaf_write_output_json(VmafContext *vmaf, VmafFeatureCollector *fc,
     fprintf(outfile, "\n  }\n");
     fprintf(outfile, "}\n");
 
+    if (c_locale != (locale_t)0) {
+        uselocale(old_locale);
+        freelocale(c_locale);
+    }
+
     return 0;
 }
 
 int vmaf_write_output_csv(VmafFeatureCollector *fc, FILE *outfile,
                            unsigned subsample)
 {
+    locale_t c_locale = newlocale(LC_ALL_MASK, "C", NULL);
+    locale_t old_locale = (locale_t)0;
+    if (c_locale != (locale_t)0) {
+        old_locale = uselocale(c_locale);
+    }
+
     int leading_zeros_count;
     fprintf(outfile, "Frame,");
     for (unsigned i = 0; i < fc->cnt; i++) {
@@ -342,12 +371,23 @@ int vmaf_write_output_csv(VmafFeatureCollector *fc, FILE *outfile,
         fprintf(outfile, "\n");
     }
 
+    if (c_locale != (locale_t)0) {
+        uselocale(old_locale);
+        freelocale(c_locale);
+    }
+
     return 0;
 }
 
 int vmaf_write_output_sub(VmafFeatureCollector *fc, FILE *outfile,
                           unsigned subsample)
 {
+    locale_t c_locale = newlocale(LC_ALL_MASK, "C", NULL);
+    locale_t old_locale = (locale_t)0;
+    if (c_locale != (locale_t)0) {
+        old_locale = uselocale(c_locale);
+    }
+
     int leading_zeros_count;
     for (unsigned i = 0 ; i < max_capacity(fc); i++) {
         if ((subsample > 1) && (i % subsample))
@@ -381,5 +421,10 @@ int vmaf_write_output_sub(VmafFeatureCollector *fc, FILE *outfile,
         fprintf(outfile, "\n");
     }
 
+    if (c_locale != (locale_t)0) {
+        uselocale(old_locale);
+        freelocale(c_locale);
+    }
+
     return 0;
 }
diff --git a/libvmaf/src/read_json_model.c b/libvmaf/src/read_json_model.c
index 08405d3b7..e7c4f8d02 100644
--- a/libvmaf/src/read_json_model.c
+++ b/libvmaf/src/read_json_model.c
@@ -24,6 +24,7 @@
 #include <errno.h>
 #include <stdlib.h>
 #include <string.h>
+#include <locale.h>
 
 #define MAX_FEATURE_COUNT 64 //FIXME
 #define MAX_KNOT_COUNT 10 //FIXME
@@ -432,6 +433,7 @@ static int model_parse(json_stream *s, VmafModel *model,
 static int vmaf_read_json_model(VmafModel **model, VmafModelConfig *cfg,
                                 json_stream *s)
 {
+    int err = -EINVAL;
     VmafModel *const m = *model = malloc(sizeof(*m));
     if (!m) return -ENOMEM;
     memset(m, 0, sizeof(*m));
@@ -449,7 +451,20 @@ static int vmaf_read_json_model(VmafModel **model, VmafModelConfig *cfg,
     if (!m->score_transform.knots.list) return -ENOMEM;
     memset(m->score_transform.knots.list, 0, knots_sz);
 
-    return model_parse(s, m, cfg->flags);
+    locale_t c_locale = newlocale(LC_ALL_MASK, "C", NULL);
+    locale_t old_locale = (locale_t)0;
+    if (c_locale != (locale_t)0) {
+        old_locale = uselocale(c_locale);
+    }
+
+    err = model_parse(s, m, cfg->flags);
+
+    if (c_locale != (locale_t)0) {
+        uselocale(old_locale);
+        freelocale(c_locale);
+    }
+
+    return err;
 }
 
 int vmaf_read_json_model_from_buffer(VmafModel **model, VmafModelConfig *cfg,
diff --git a/libvmaf/src/svm.cpp b/libvmaf/src/svm.cpp
index 94d3379d8..5ea8c02e7 100644
--- a/libvmaf/src/svm.cpp
+++ b/libvmaf/src/svm.cpp
@@ -2653,11 +2653,11 @@ int svm_save_model(const char *model_file_name, const svm_model *model)
 	FILE *fp = fopen(model_file_name,"w");
 	if(fp==NULL) return -1;
 
-	char *old_locale = setlocale(LC_ALL, NULL);
-	if (old_locale) {
-		old_locale = strdup(old_locale);
+	locale_t c_locale = newlocale(LC_ALL_MASK, "C", NULL);
+	locale_t old_locale = (locale_t)0;
+	if (c_locale != (locale_t)0) {
+		old_locale = uselocale(c_locale);
 	}
-	setlocale(LC_ALL, "C");
 
 	const svm_parameter& param = model->param;
 
@@ -2738,8 +2738,10 @@ int svm_save_model(const char *model_file_name, const svm_model *model)
 		fprintf(fp, "\n");
 	}
 
-	setlocale(LC_ALL, old_locale);
-	free(old_locale);
+	if (c_locale != (locale_t)0) {
+		uselocale(old_locale);
+		freelocale(c_locale);
+	}
 
 	if (ferror(fp) != 0 || fclose(fp) != 0) return -1;
 	else return 0;