diff --git a/video/image_writer.c b/video/image_writer.c
index 491828aa22..88ffb7964c 100644
--- a/video/image_writer.c
+++ b/video/image_writer.c
@@ -78,14 +78,14 @@ struct image_writer_ctx {
 
 struct img_writer {
     const char *file_ext;
-    int (*write)(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp);
+    bool (*write)(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp);
     const int *pixfmts;
     int lavc_codec;
 };
 
-static int write_lavc(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp)
+static bool write_lavc(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp)
 {
-    int success = 0;
+    bool success = 0;
     AVFrame *pic = NULL;
     AVPacket pkt = {0};
     int got_output = 0;
@@ -161,7 +161,7 @@ static void write_jpeg_error_exit(j_common_ptr cinfo)
   longjmp(*(jmp_buf*)cinfo->client_data, 1);
 }
 
-static int write_jpeg(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp)
+static bool write_jpeg(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp)
 {
     struct jpeg_compress_struct cinfo;
     struct jpeg_error_mgr jerr;
@@ -173,7 +173,7 @@ static int write_jpeg(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp)
     cinfo.client_data = &error_return_jmpbuf;
     if (setjmp(cinfo.client_data)) {
         jpeg_destroy_compress(&cinfo);
-        return 0;
+        return false;
     }
 
     jpeg_create_compress(&cinfo);
@@ -209,7 +209,7 @@ static int write_jpeg(struct image_writer_ctx *ctx, mp_image_t *image, FILE *fp)
 
     jpeg_destroy_compress(&cinfo);
 
-    return 1;
+    return true;
 }
 
 #endif
@@ -279,8 +279,8 @@ const char *image_writer_file_ext(const struct image_writer_opts *opts)
     return get_writer(opts)->file_ext;
 }
 
-int write_image(struct mp_image *image, const struct image_writer_opts *opts,
-                const char *filename, struct mp_log *log)
+bool write_image(struct mp_image *image, const struct image_writer_opts *opts,
+                 const char *filename, struct mp_log *log)
 {
     struct mp_image *allocated_image = NULL;
     struct image_writer_opts defs = image_writer_opts_defaults;
@@ -316,7 +316,7 @@ int write_image(struct mp_image *image, const struct image_writer_opts *opts,
     }
 
     FILE *fp = fopen(filename, "wb");
-    int success = 0;
+    bool success = false;
     if (fp == NULL) {
         mp_err(log, "Error opening '%s' for writing!\n", filename);
     } else {
diff --git a/video/image_writer.h b/video/image_writer.h
index 7db4293712..d7cdd99125 100644
--- a/video/image_writer.h
+++ b/video/image_writer.h
@@ -48,8 +48,8 @@ const char *image_writer_file_ext(const struct image_writer_opts *opts);
  *       accordingly. Setting w and width or h and height to different values
  *       can be used to store snapshots of anamorphic video.
  */
-int write_image(struct mp_image *image, const struct image_writer_opts *opts,
-                const char *filename, struct mp_log *log);
+bool write_image(struct mp_image *image, const struct image_writer_opts *opts,
+                 const char *filename, struct mp_log *log);
 
 // Debugging helper.
 void dump_png(struct mp_image *image, const char *filename, struct mp_log *log);