[FFmpeg-devel] [PATCH] avfilter/vf_libvmaf: fix string comparison bug

[Nil Fons Miret]

The libvmaf filter was doing substring checks in place of string
equality comparisons. This led to a bug when the user specified the
pooling method "harmonic_mean", since "mean" was checked first and the
substring comparison returned true. This patch changes all substring
comparisons for string equality comparisons. This is both correct and
more efficient than the existing method.

Signed-off-by: nilfm <nilf at netflix.com>
---
libavfilter/vf_libvmaf.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/libavfilter/vf_libvmaf.c b/libavfilter/vf_libvmaf.c
index 12810b7267..46ff8154ef 100644
--- a/libavfilter/vf_libvmaf.c
+++ b/libavfilter/vf_libvmaf.c
@@ -251,7 +251,7 @@ static int parse_features(AVFilterContext *ctx)
        const AVDictionaryEntry *e = NULL;

        while (e = av_dict_iterate(dict[i], e)) {
-            if (av_stristr(e->key, "name")) {
+            if (!strcmp(e->key, "name")) {
                feature_name = e->value;
                continue;
            }
@@ -312,29 +312,29 @@ static int parse_models(AVFilterContext *ctx)
        char  *path = NULL;

        while (e = av_dict_iterate(dict[i], e)) {
-            if (av_stristr(e->key, "disable_clip")) {
-                model_cfg.flags |= av_stristr(e->value, "true") ?
+            if (!strcmp(e->key, "disable_clip")) {
+                model_cfg.flags |= !strcmp(e->value, "true") ?
                    VMAF_MODEL_FLAG_DISABLE_CLIP : 0;
                continue;
            }

-            if (av_stristr(e->key, "enable_transform")) {
-                model_cfg.flags |= av_stristr(e->value, "true") ?
+            if (!strcmp(e->key, "enable_transform")) {
+                model_cfg.flags |= !strcmp(e->value, "true") ?
                    VMAF_MODEL_FLAG_ENABLE_TRANSFORM : 0;
                continue;
            }

-            if (av_stristr(e->key, "name")) {
+            if (!strcmp(e->key, "name")) {
                model_cfg.name = e->value;
                continue;
            }

-            if (av_stristr(e->key, "version")) {
+            if (!strcmp(e->key, "version")) {
                version = e->value;
                continue;
            }

-            if (av_stristr(e->key, "path")) {
+            if (!strcmp(e->key, "path")) {
                path = e->value;
                continue;
            }
@@ -529,13 +529,13 @@ static int activate(AVFilterContext *ctx)
static enum VmafOutputFormat log_fmt_map(const char *log_fmt)
{
    if (log_fmt) {
-        if (av_stristr(log_fmt, "xml"))
+        if (!strcmp(log_fmt, "xml"))
            return VMAF_OUTPUT_FORMAT_XML;
-        if (av_stristr(log_fmt, "json"))
+        if (!strcmp(log_fmt, "json"))
            return VMAF_OUTPUT_FORMAT_JSON;
-        if (av_stristr(log_fmt, "csv"))
+        if (!strcmp(log_fmt, "csv"))
            return VMAF_OUTPUT_FORMAT_CSV;
-        if (av_stristr(log_fmt, "sub"))
+        if (!strcmp(log_fmt, "sub"))
            return VMAF_OUTPUT_FORMAT_SUB;
    }

@@ -545,11 +545,11 @@ static enum VmafOutputFormat log_fmt_map(const
char *log_fmt)
static enum VmafPoolingMethod pool_method_map(const char *pool_method)
{
    if (pool_method) {
-        if (av_stristr(pool_method, "min"))
+        if (!strcmp(pool_method, "min"))
            return VMAF_POOL_METHOD_MIN;
-        if (av_stristr(pool_method, "mean"))
+        if (!strcmp(pool_method, "mean"))
            return VMAF_POOL_METHOD_MEAN;
-        if (av_stristr(pool_method, "harmonic_mean"))
+        if (!strcmp(pool_method, "harmonic_mean"))
            return VMAF_POOL_METHOD_HARMONIC_MEAN;
    }

-- 
2.37.1 (Apple Git-137.1)