avoid some false positives in png extraction

src/pngv3.ts

@@ -61,7 +61,7 @@ const extractFromRawDeflate = (b: Buffer) => {
     const hidden = new BitstreamWriter({
         write(chunk) {
             for (const i of chunk) {
-                if (i)
+                if (i >= 0x20 && i <= 128) // only printable ascii
                     chnks.push(i);
                 else
                     throw "Finish";
@@ -234,9 +234,8 @@ const extract = async (png: Buffer, doextract = true) => {
                 .toString()
                 .split(' ')
                 .map(e => {
-                    if (!(e[0] in rprefs))
+                    if (!(e[0] in rprefs) || e[1].length < 5) // link needs to be long enough, avoid false positives
                         throw "Uhh";
-                    // should also check if the id has a len of 6-8 or ends in .pee
                     return `https://${rprefs[e[0]]}/${e.slice(1)}`;
                 }).join(' ');
             if (doextract)