+static int jpeg_probe(AVProbeData *p)
+{
+ const uint8_t *b = p->buf;
+ int i, state = 0xD8;
+
+ if (AV_RB16(b) != 0xFFD8 ||
+ AV_RB32(b) == 0xFFD8FFF7)
+ return 0;
+
+ b += 2;
+ for (i = 0; i < p->buf_size - 2; i++) {
+ int c;
+ if (b[i] != 0xFF)
+ continue;
+ c = b[i + 1];
+ switch (c) {
+ case 0xD8:
+ return 0;
+ case 0xC0:
+ case 0xC1:
+ case 0xC2:
+ case 0xC3:
+ case 0xC5:
+ case 0xC6:
+ case 0xC7:
+ if (state != 0xD8)
+ return 0;
+ state = 0xC0;
+ break;
+ case 0xDA:
+ if (state != 0xC0)
+ return 0;
+ state = 0xDA;
+ break;
+ case 0xD9:
+ if (state != 0xDA)
+ return 0;
+ state = 0xD9;
+ break;
+ default:
+ if ( (c >= 0x02 && c <= 0xBF)
+ || c == 0xC8)
+ return 0;
+ }
+ }
+
+ if (state == 0xD9)
+ return AVPROBE_SCORE_EXTENSION + 1;
+ return AVPROBE_SCORE_EXTENSION / 8;
+}
+