static int find_unused_picture(MpegEncContext *s, int shared) { int i; if (shared) { for (i = 0; i < MAX_PICTURE_COUNT; i++) { if (s->picture[i].f.data[0] == NULL) return i; } } else { for (i = 0; i < MAX_PICTURE_COUNT; i++) { if (pic_is_unused(s, &s->picture[i])) return i; } } return AVERROR_INVALIDDATA; }